A privacy-protected mobile phone return incentive method, device and storage medium

Abstract

The present invention belongs to the field of computer technology, and in particular, relates to a privacy-protected mobile phone return incentive method, device, and storage medium. Using smart contract technology, registering a mobile phone account address, transferring the reward based on the mobile phone account address and the returner's reward collection address and automatically executing transactions, using a return device as an intermediary for returning the mobile phone, building trust without third-party guarantees, and using a retrieval program to display the reward without telephone communication, eliminating the need for telephone negotiation and recording the reward to avoid the returner's on-the-spot price increase. Returning the mobile phone through the return device also avoids the returner's behavior of receiving the reward and refusing to return it. The reward is pre-deposited in the mobile phone account address to ensure that the owner pays the reward. The incentive method of this scheme uses rewards to incentivize the behavior of returning the mobile phone and solves the trust problem during return through blockchain technology combined with the return device.

Description

Technical Field

[0001] The present invention belongs to the field of computer technology, and in particular relates to a privacy-protected mobile phone return incentive method, device and storage medium. Background Art

[0002] The role of mobile phones in daily life has become increasingly important. In addition to the risk to various social accounts and payment accounts, losing a mobile phone will also cause the loss of personal information such as personal photos. Once a mobile phone is lost, it will have a great impact on all aspects of the user's life. In the existing technology, the traditional method of searching by mobile phone signal or appearance is considered. Even if combined with blockchain, it only registers information similar to photos and broadcasts the search. However, if the person who found it is unwilling to return it, the user will not be able to get his lost mobile phone. Therefore, in most cases, the person who finds the lost mobile phone often waits for the owner to call in so that he can get in touch with the owner. However, sometimes some people who find the mobile phone are unwilling to return the mobile phone to the owner directly for free, but want to ask for a reward. If they cannot get the reward, they will turn off the phone or even try to crack the password of the mobile phone.

[0003] There is basically no trust between the two parties in this kind of reward transaction. They can only rely on their trust in the other party's character. If both parties can fulfill their promises in telephone communication, the reward transaction can be completed well. However, in reality, there are more cases where the person returning the mobile phone suddenly changes his mind and increases the price on the originally agreed reward in order to seek a higher reward, or is unwilling to return the mobile phone after receiving the reward, or the owner is unwilling to pay the reward after receiving the mobile phone, and so on.

[0004] In fact, a lost mobile phone is not only valuable to the owner as it contains more information and data. However, to the finder, the phone is at most a second-hand phone. In addition, since some existing mobile phones have a lost mode that directly locks the phone, the finder cannot use it. In the hands of the finder, it may be as useless as a brick. Therefore, is it possible to propose an incentive method for returning mobile phones to encourage the finder to become the returner, which can better solve the trust problem between the owner and the returner? Summary of the invention

[0005] In order to solve the above problems, the present invention provides a blockchain-based mobile phone return incentive method, device and storage medium, which can incentivize the return of mobile phones, obtain certain rewards and solve the trust problem between the returner and the owner.

[0006] The present invention adopts the following technical solutions.

[0007] In the first aspect, a privacy-protected mobile phone return incentive method is provided, including the following contents:

[0008] The roles of the method include: a blockchain system, a retrieval program installed on a mobile phone, a returner, an owner, and a returned device;

[0009] The blockchain system is deployed with a mobile phone retrieval contract, which allows the owner to register a mobile phone account address. The mobile phone retrieval contract is configured with a collection tree and a second zero-knowledge proof circuit. The collection tree is used to store the collection hash, and the mobile phone account address is stored in the retrieval program. The retrieval program is used to lock the mobile phone when it is lost and display the retrieval information set by the owner. The return device includes a data synchronization module for synchronizing blockchain system information; a mobile phone locking module for locking or unlocking the returned mobile phone; an address identification module for identifying the mobile phone account address in the retrieval program; a transaction issuance module for sending and signing a mobile phone return transaction; a zero-knowledge circuit module for generating a first zero-knowledge proof based on the returner's first public input and first private input and publishing the first public input and the first zero-knowledge proof;

[0010] The method comprises:

[0011] The lost first mobile phone receives a lost instruction sent by the owner and enters a lost mode, the retrieval program locks the first mobile phone and displays the retrieval information set by the owner on the screen, the retrieval information includes the first reward amount;

[0012] Based on the mobile phone retrieval contract, the owner transfers the second reward to the retrieval address of the mobile phone retrieval contract through the mobile phone account address and attaches the retrieval hash, which is generated locally by the owner based on the retrieval password;

[0013] The returner puts the first mobile phone into the return device, and inputs the first zero-knowledge proof information for the returner to collect the second reward through the zero-knowledge circuit module, wherein the first zero-knowledge proof information includes a first public input and a first private input, wherein the first public input includes the first reward amount and the first collection hash, and the first private input includes a first random number, which is selected locally by the returner, and the first collection hash is obtained by performing a hash operation on the first reward amount and the first random number;

[0014] The mobile phone locking module of the returned device locks the first mobile phone placed therein;

[0015] The address identification module of the returned device identifies the mobile phone account address stored in the retrieval program in the first mobile phone;

[0016] The transaction issuance module for returning the device constructs and signs a mobile phone return transaction based on the mobile phone account address and the first collection hash, and sends the mobile phone return transaction to the blockchain system;

[0017] The mobile phone return contract receives the mobile phone return transaction, verifies the first claim hash based on the amount of the second reward and the first random number of the first private input, and if the verification is successful, stores the first claim hash in the claim tree;

[0018] The data synchronization module of the returned device synchronizes the retrieval hash attached to the reward;

[0019] The mobile phone locking module of the returned device sets the retrieved hash as the unlocked hash of the first mobile phone;

[0020] The owner enters the retrieval password at the returned device to recalculate the retrieval hash, and the returned device verifies whether the recalculated retrieval hash is consistent with the unlocking hash. If they are consistent, the first mobile phone is unlocked;

[0021] The returner initiates a zero-knowledge proof transaction, which includes a second public input and a second private input. The second public input includes a claim tree root hash, the amount of a second reward, and an invalid hash. The second private input includes a first claim hash, a first claim tree path, and a first random number. The invalid hash is obtained by hashing the first claim hash. The first claim tree path is the path data of the first claim hash in the claim tree. Based on the execution of the zero-knowledge proof transaction, the second public input and the second private input are used to generate a second zero-knowledge proof through a second zero-knowledge circuit. The blockchain system verifies the second zero-knowledge proof. If the verification is passed, the returner receives the second reward corresponding to the first claim hash.

[0022] Preferably, the return device also includes a positioning module for generating location information of the return device. The mobile phone return transaction constructed by the transaction issuance module also includes the location information of the return device. Based on the execution of the mobile phone return transaction, the location information of the return device is sent to the mobile phone account address.

[0023] In a second aspect, a computer device is provided, comprising one or more processors;

[0024] a memory for storing one or more programs,

[0025] When the one or more programs are executed by the one or more processors, the one or more processors execute the method as described in the first aspect above.

[0026] According to a third aspect, a storage medium storing a computer program is provided, and when the program is executed by a processor, the method described in the first aspect is implemented.

[0027] The beneficial effect of the present invention is that the blockchain technology is applied to the scenario of returning a lost mobile phone, the smart contract technology is used to register the mobile phone account address, and the reward is transferred by automatically executing transactions based on the mobile phone account address and the returner's reward collection address, and the return device is used as an intermediary for returning the mobile phone to build trust without third-party guarantee. At the same time, the reward is displayed using the retrieval program, and no telephone communication is required. The telephone negotiation process is eliminated and the reward is recorded to avoid the returner's on-the-spot price increase. Returning the mobile phone through the return device also avoids the returner's collection of rewards and refusing to return it. The reward is pre-deposited in the mobile phone account address to ensure that the owner pays the reward. The incentive method of this scheme incentivizes the behavior of returning the mobile phone through the reward and solves the trust problem at the time of return through the blockchain technology combined with the return device. On the other hand, the scheme of the present invention uses the first zero-knowledge proof to set the collection hash for the reward, and collects the reward through the zero-knowledge proof transaction, which can effectively protect the privacy of the returner and avoid tracing it by the blockchain address. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of the structure of a computer device according to Embodiment 2 of the present invention. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with specific embodiments and the accompanying drawings. Those of ordinary skill in the art will be able to implement the present invention based on these descriptions. In addition, the embodiments of the present invention involved in the following description are generally only embodiments of a part of the present invention, rather than all embodiments. Therefore, based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work should fall within the scope of protection of the present invention. Unless otherwise specified, the methods briefly described in the embodiments of the present invention are methods mastered by those skilled in the art.

[0030] Example 1

[0031] This embodiment provides a privacy-protected mobile phone return incentive method, including the following contents:

[0032] The roles of the method include: a blockchain system, a retrieval program installed on a mobile phone, a returner, an owner, and a returned device;

[0033] The blockchain system is deployed with a mobile phone retrieval contract, which allows the owner to register a mobile phone account address. The mobile phone retrieval contract is configured with a collection tree and a second zero-knowledge proof circuit. The collection tree is used to store the collection hash, and the mobile phone account address is stored in the retrieval program. The retrieval program is used to lock the mobile phone when it is lost and display the retrieval information set by the owner. The return device includes a data synchronization module for synchronizing blockchain system information; a mobile phone locking module for locking or unlocking the returned mobile phone; an address identification module for identifying the mobile phone account address in the retrieval program; a transaction issuance module for sending and signing a mobile phone return transaction; a zero-knowledge circuit module for generating a first zero-knowledge proof based on the returner's first public input and first private input and publishing the first public input and the first zero-knowledge proof;

[0034] The method comprises:

[0035] The lost first mobile phone receives a lost instruction sent by the owner and enters a lost mode, the retrieval program locks the first mobile phone and displays the retrieval information set by the owner on the screen, the retrieval information includes the first reward amount;

[0036] Based on the mobile phone retrieval contract, the owner transfers the second reward to the retrieval address of the mobile phone retrieval contract through the mobile phone account address and attaches the retrieval hash, which is generated locally by the owner based on the retrieval password;

[0037] The returner puts the first mobile phone into the return device, and inputs the first zero-knowledge proof information for the returner to collect the second reward through the zero-knowledge circuit module, wherein the first zero-knowledge proof information includes a first public input and a first private input, wherein the first public input includes the first reward amount and the first collection hash, and the first private input includes a first random number, which is selected locally by the returner, and the first collection hash is obtained by performing a hash operation on the first reward amount and the first random number;

[0038] The mobile phone locking module of the returned device locks the first mobile phone placed therein;

[0039] The address identification module of the returned device identifies the mobile phone account address stored in the retrieval program in the first mobile phone;

[0040] The transaction issuance module for returning the device constructs and signs a mobile phone return transaction based on the mobile phone account address and the first collection hash, and sends the mobile phone return transaction to the blockchain system;

[0041] The mobile phone return contract receives the mobile phone return transaction, verifies the first claim hash based on the amount of the second reward and the first random number of the first private input, and if the verification is successful, stores the first claim hash in the claim tree;

[0042] The data synchronization module of the returned device synchronizes the retrieval hash attached to the reward;

[0043] The mobile phone locking module of the returned device sets the retrieved hash as the unlocked hash of the first mobile phone;

[0044] The owner enters the retrieval password at the returned device to recalculate the retrieval hash, and the returned device verifies whether the recalculated retrieval hash is consistent with the unlocking hash. If they are consistent, the first mobile phone is unlocked;

[0045] The returner initiates a zero-knowledge proof transaction, which includes a second public input and a second private input. The second public input includes a claim tree root hash, the amount of a second reward, and an invalid hash. The second private input includes a first claim hash, a first claim tree path, and a first random number. The invalid hash is obtained by hashing the first claim hash. The first claim tree path is the path data of the first claim hash in the claim tree. Based on the execution of the zero-knowledge proof transaction, the second public input and the second private input are used to generate a second zero-knowledge proof through a second zero-knowledge circuit. The blockchain system verifies the second zero-knowledge proof. If the verification is passed, the returner receives the second reward corresponding to the first claim hash.

[0046] Furthermore, the return device also includes a positioning module for generating location information of the return device. The mobile phone return transaction constructed by the transaction issuance module also includes the location information of the return device. Based on the execution of the mobile phone return transaction, the location information of the return device is sent to the mobile phone account address.

[0047] In this embodiment, the lost mobile phone is installed with a blockchain wallet, and the retrieval program is integrated in the blockchain wallet. The wallet supports lost mode. In lost mode, the mobile phone will be locked and the retrieval information set by the owner will be output to the main screen of the mobile phone lock screen. In this embodiment, the retrieval information includes QR code information and certain text information. The text information is the number of reward tokens entered by the mobile phone owner through the blockchain lost contract. The owner can enter this number multiple times, and the cumulative reward number is displayed. When the user offers a reward for the first time, such as 500 tokens, and it has not been retrieved for a certain period of time, the user can continue to add to increase the possibility of retrieval. When the owner enters the reward, a retrieval hash is attached. The retrieval hash = hash (retrieval password). This password is known by the user himself and is used to unlock the retrieval hash. The longer it is, the safer it is. The QR code information is the public key address of the user's wallet. The blockchain deploys a mobile phone return contract, allowing the owner to register a mobile phone account address. This address is bound to the mobile phone blockchain wallet. The owner uses the private signature of the mobile phone account address to enter the reward number of tokens to the retrieval address and lock it. After the returner sees the retrieval information and is willing to return the phone, he finds a return phone device. The returner enters the reward token number displayed on the phone screen and the first random number generated locally in the return device. At this time, the return device automatically generates the first collection hash for input and outputs the first zero-knowledge proof. The token number entered by the returner and the first collection hash are used as the public input of the first zero-knowledge proof and are announced together with the first zero-knowledge proof. The first collection hash is obtained by hashing the token number entered by the returner and the first random number.

[0048] The returner puts the phone into the return device, and the return device locks the phone. After confirming the lock, the return device scans the mobile wallet address and sends a mobile phone return transaction. The transaction is accompanied by the first zero-knowledge proof and the mobile phone account address, and the location information of the return device is attached for easy search. After receiving the mobile phone return transaction, the return contract searches for the reward according to the mobile phone account address, and hashes the amount of the reward with the first random number entered by the returner to verify the first zero-knowledge proof. If the verification is successful, the first collection hash is stored in the collection tree, and the retrieval hash attached to the reward is used as the unlock hash of the phone. The owner picks up the phone according to the location information of the return device, enters the retrieval password, and the retrieval device calculates the hash of the password and verifies whether it is consistent with the unlock hash. If it is consistent, the door is opened and the user takes out the phone.

[0049] The returner initiates a zero-knowledge proof transaction to claim the reward. Based on the mobile phone return contract, the reward of the mobile phone is deposited into the contract account and the corresponding claim hash, i.e., the first claim hash, is set. Only those who know the claim hash can claim the reward, i.e., transfer the reward to the set address. Because the claim hash needs to be verified to claim the reward, the claim address can be hidden. The zero-knowledge proof transaction verifies that the transaction proposer, i.e., the returner, knows the first claim hash through the second zero-knowledge proof. The second zero-knowledge proof is obtained based on the second zero-knowledge circuit through the second public input and the second private input. The second public input includes the claim tree root hash, the number of tokens input by the returner, and the invalid hash. The second private input includes the first claim hash, the first claim tree path, and the first random number. The invalid hash is obtained by hashing the first claim hash. The first claim tree path is the first claim hash in the claim Take the path data in the tree, first verify whether the invalid hash exists. If the invalid hash exists, it proves that the claim hash has been used, and no subsequent verification is required. If the invalid hash has not been used, the claim tree root hash is calculated through the first claim hash and the first claim tree path in the second private input. The root hash of the claim tree can be obtained through the claim tree. The claim tree is public, so everyone can verify whether the claim tree root hash is accurate. If the calculated claim tree root hash is consistent with the public data, it means that the first claim hash is indeed on the claim tree, then the returner has the right to claim the reward corresponding to the first claim hash. The returner then sets the claim address and collects the reward in the contract's retrieval address to the claim address. The outside world can only see that someone has provided a zero-knowledge proof to prove that they own the claim hash and have received the reward but will not know the corresponding claim address, but can verify the zero-knowledge proof.

[0050] The scheme of this embodiment applies blockchain technology to the scenario of returning a lost mobile phone, uses smart contract technology to register a mobile phone account address, and automatically executes transactions to transfer rewards based on the mobile phone account address and the returner's reward collection address. The return device is used as an intermediary for returning the mobile phone to build trust without third-party guarantees. At the same time, the reward is displayed using a retrieval program, and no telephone communication is required. The reward is recorded while the telephone negotiation process is eliminated to avoid the returner's on-the-spot price increase. Returning the mobile phone through the return device also avoids the returner's behavior of collecting rewards and refusing to return it. The reward is pre-deposited in the mobile phone account address to ensure that the owner pays the reward. The incentive method of this scheme incentivizes the behavior of returning the mobile phone through rewards and solves the trust problem during return through blockchain technology combined with the return device. On the other hand, the scheme of this embodiment uses the first zero-knowledge proof to set a collection hash for the reward, and collects the reward through a zero-knowledge proof transaction, which can effectively protect the privacy of the returner and avoid tracing it by the blockchain address.

[0051] Example 2

[0052] A computer device comprises: one or more processors; and a memory for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors execute the method described in Example 1.

[0053] A storage medium storing a computer program, which, when executed by a processor, implements the method described in the above embodiment 1.

[0054] Figure 1 A schematic diagram of the structure of a device provided in this embodiment.

[0055] like Figure 1 As shown, as another aspect, the present application also provides a computer device 500, including one or more central processing units (CPU) 501, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 502 or the program loaded from the storage part 508 to the random access memory (RAM) 503. In the RAM 503, various programs and data required for the operation of the device 500 are also stored. The CPU 501, the ROM 502, and the RAM 503 are connected to each other via a bus 504. An input / output (I / O) interface 505 is also connected to the bus 504.

[0056] The following components are connected to the I / O interface 505: an input section 506 including a keyboard, a mouse, etc.; an output section 507 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker, etc.; a storage section 508 including a hard disk, etc.; and a communication section 509 including a network interface card such as a LAN card, a modem, etc. The communication section 509 performs communication processing via a network such as the Internet. A driver 510 is also connected to the I / O interface 505 as needed. A removable medium 511, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the driver 510 as needed, so that a computer program read therefrom is installed into the storage section 508 as needed.

[0057] In particular, according to the embodiments disclosed in the present application, the method described in the above embodiment 1 can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program tangibly contained on a machine-readable medium, and the computer program includes a program code for executing the method described in any of the above embodiments. In such an embodiment, the computer program can be downloaded and installed from a network through the communication part 509, and / or installed from the removable medium 511.

[0058] As another aspect, the present application further provides a computer-readable storage medium, which may be a computer-readable storage medium included in the apparatus of the above embodiment; or a computer-readable storage medium that exists independently and is not assembled into the device. The computer-readable storage medium stores one or more programs, which are used by one or more processors to execute the method described in the present application.

[0059] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present invention. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be realized by a dedicated hardware-based system that performs a specified function or operation, or can be realized by a combination of dedicated hardware and computer instructions.

[0060] The units or modules involved in the embodiments described in the present application may be implemented by software or by hardware. The units or modules described may also be arranged in a processor. For example, each of the units may be a software program arranged in a computer or a mobile smart device, or may be a separately configured hardware device. The names of these units or modules do not, in some cases, constitute limitations on the units or modules themselves.

[0061] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the concept of the present application. For example, the above features are replaced with the technical features with similar functions disclosed in the present application (but not limited to) to form a technical solution.

Claims

1. A privacy-protected mobile phone return incentive method, characterized in that: It includes the following: The roles of the method include: a blockchain system, a retrieval program installed on a mobile phone, a returner, an owner, and a returned device; The blockchain system is deployed with a mobile phone retrieval contract, which allows the owner to register a mobile phone account address. The mobile phone retrieval contract is configured with a collection tree and a second zero-knowledge proof circuit. The collection tree is used to store the collection hash, and the mobile phone account address is stored in the retrieval program. The retrieval program is used to lock the mobile phone when it is lost and display the retrieval information set by the owner. The return device includes a data synchronization module for synchronizing blockchain system information; a mobile phone locking module for locking or unlocking the returned mobile phone; an address identification module for identifying the mobile phone account address in the retrieval program; a transaction issuance module for sending and signing a mobile phone return transaction; a zero-knowledge circuit module for generating a first zero-knowledge proof based on the returner's first public input and first private input and publishing the first public input and the first zero-knowledge proof; The method comprises: The lost first mobile phone receives a lost instruction sent by the owner and enters a lost mode, the retrieval program locks the first mobile phone and displays the retrieval information set by the owner on the screen, the retrieval information includes the first reward amount; Based on the mobile phone retrieval contract, the owner transfers the second reward to the retrieval address of the mobile phone retrieval contract through the mobile phone account address and attaches the retrieval hash, which is generated locally by the owner based on the retrieval password; The returner puts the first mobile phone into the return device, and inputs the first zero-knowledge proof information for the returner to collect the second reward through the zero-knowledge circuit module, wherein the first zero-knowledge proof information includes a first public input and a first private input, wherein the first public input includes the first reward amount and the first collection hash, and the first private input includes a first random number, which is selected locally by the returner, and the first collection hash is obtained by performing a hash operation on the first reward amount and the first random number; The mobile phone locking module of the returned device locks the first mobile phone placed therein; The address identification module of the returned device identifies the mobile phone account address stored in the retrieval program in the first mobile phone; The transaction issuance module for returning the device constructs and signs a mobile phone return transaction based on the mobile phone account address and the first collection hash, and sends the mobile phone return transaction to the blockchain system; The mobile phone return contract receives the mobile phone return transaction, verifies the first claim hash based on the amount of the second reward and the first random number of the first private input, and if the verification is successful, stores the first claim hash in the claim tree; The data synchronization module of the returned device synchronizes the retrieval hash attached to the reward; The mobile phone locking module of the returned device sets the retrieved hash as the unlocked hash of the first mobile phone; The owner enters the retrieval password at the returned device to recalculate the retrieval hash, and the returned device verifies whether the recalculated retrieval hash is consistent with the unlocking hash. If they are consistent, the first mobile phone is unlocked; The returner initiates a zero-knowledge proof transaction, which includes a second public input and a second private input. The second public input includes a claim tree root hash, the amount of a second reward, and an invalid hash. The second private input includes a first claim hash, a first claim tree path, and a first random number. The invalid hash is obtained by hashing the first claim hash. The first claim tree path is the path data of the first claim hash in the claim tree. Based on the execution of the zero-knowledge proof transaction, the second public input and the second private input are used to generate a second zero-knowledge proof through a second zero-knowledge circuit. The blockchain system verifies the second zero-knowledge proof. If the verification is passed, the returner receives the second reward corresponding to the first claim hash.

2. A privacy-protected mobile phone return incentive method according to claim 1, characterized in that: The return device also includes a positioning module for generating location information of the return device. The mobile phone return transaction constructed by the transaction issuance module also includes the location information of the return device. Based on the execution of the mobile phone return transaction, the location information of the return device is sent to the mobile phone account address.

3. A computer device, characterized in that: one or more processors; a memory for storing one or more programs, When the one or more programs are executed by the one or more processors, the one or more processors are caused to perform the method according to claim 1 or 2.

4. A storage medium storing a computer program, characterized in that: When the program is executed by a processor, the method according to claim 1 or 2 is implemented.

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