// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.9;

import "@thirdweb-dev/contracts/extension/PermissionsEnumerable.sol";
import "@openzeppelin/contracts/token/ERC721/IERC721.sol";
import "@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol";



contract InvisibleFriendsBurnContract is IERC721Receiver, PermissionsEnumerable{
    
    bytes32 public constant TRANSFER_ROLE = keccak256("TRANSFER_ROLE");

    constructor() {
        _setupRole(DEFAULT_ADMIN_ROLE, msg.sender);
        _setupRole(TRANSFER_ROLE, msg.sender);
    }

    function onERC721Received(
        address,
        address,
        uint256,
        bytes memory
    ) external view override returns (bytes4) {
        return IERC721Receiver.onERC721Received.selector;
    }

    function transferIERC721(address nft, uint256 _tokenId, address _from, address _to) public onlyRole(TRANSFER_ROLE) {
        IERC721 nftAddress = IERC721(nft);
        nftAddress.safeTransferFrom(_from, _to,_tokenId);
    }


}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[EIP].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165 {
    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC721/IERC721.sol)

pragma solidity ^0.8.0;

import "../../utils/introspection/IERC165.sol";

/**
 * @dev Required interface of an ERC721 compliant contract.
 */
interface IERC721 is IERC165 {
    /**
     * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
     */
    event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);

    /**
     * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
     */
    event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);

    /**
     * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
     */
    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    /**
     * @dev Returns the number of tokens in ``owner``'s account.
     */
    function balanceOf(address owner) external view returns (uint256 balance);

    /**
     * @dev Returns the owner of the `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function ownerOf(uint256 tokenId) external view returns (address owner);

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes calldata data
    ) external;

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
     * are aware of the ERC721 protocol to prevent tokens from being forever locked.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must have been allowed to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

    /**
     * @dev Transfers `tokenId` token from `from` to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

    /**
     * @dev Gives permission to `to` to transfer `tokenId` token to another account.
     * The approval is cleared when the token is transferred.
     *
     * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
     *
     * Requirements:
     *
     * - The caller must own the token or be an approved operator.
     * - `tokenId` must exist.
     *
     * Emits an {Approval} event.
     */
    function approve(address to, uint256 tokenId) external;

    /**
     * @dev Approve or remove `operator` as an operator for the caller.
     * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
     *
     * Requirements:
     *
     * - The `operator` cannot be the caller.
     *
     * Emits an {ApprovalForAll} event.
     */
    function setApprovalForAll(address operator, bool _approved) external;

    /**
     * @dev Returns the account approved for `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function getApproved(uint256 tokenId) external view returns (address operator);

    /**
     * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
     *
     * See {setApprovalForAll}
     */
    function isApprovedForAll(address owner, address operator) external view returns (bool);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)

pragma solidity ^0.8.0;

/**
 * @title ERC721 token receiver interface
 * @dev Interface for any contract that wants to support safeTransfers
 * from ERC721 asset contracts.
 */
interface IERC721Receiver {
    /**
     * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
     * by `operator` from `from`, this function is called.
     *
     * It must return its Solidity selector to confirm the token transfer.
     * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
     *
     * The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.
     */
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

/**
 * @dev External interface of AccessControl declared to support ERC165 detection.
 */
interface IPermissions {
    /**
     * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
     *
     * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
     * {RoleAdminChanged} not being emitted signaling this.
     *
     * _Available since v3.1._
     */
    event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);

    /**
     * @dev Emitted when `account` is granted `role`.
     *
     * `sender` is the account that originated the contract call, an admin role
     * bearer except when using {AccessControl-_setupRole}.
     */
    event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Emitted when `account` is revoked `role`.
     *
     * `sender` is the account that originated the contract call:
     *   - if using `revokeRole`, it is the admin role bearer
     *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
     */
    event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) external view returns (bool);

    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {AccessControl-_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) external view returns (bytes32);

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function grantRole(bytes32 role, address account) external;

    /**
     * @dev Revokes `role` from `account`.
     *
     * If `account` had been granted `role`, emits a {RoleRevoked} event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function revokeRole(bytes32 role, address account) external;

    /**
     * @dev Revokes `role` from the calling account.
     *
     * Roles are often managed via {grantRole} and {revokeRole}: this function's
     * purpose is to provide a mechanism for accounts to lose their privileges
     * if they are compromised (such as when a trusted device is misplaced).
     *
     * If the calling account had been granted `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `account`.
     */
    function renounceRole(bytes32 role, address account) external;
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "./IPermissions.sol";

/**
 * @dev External interface of AccessControlEnumerable declared to support ERC165 detection.
 */
interface IPermissionsEnumerable is IPermissions {
    /**
     * @dev Returns one of the accounts that have `role`. `index` must be a
     * value between 0 and {getRoleMemberCount}, non-inclusive.
     *
     * Role bearers are not sorted in any particular way, and their ordering may
     * change at any point.
     *
     * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
     * you perform all queries on the same block. See the following
     * [forum post](https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296)
     * for more information.
     */
    function getRoleMember(bytes32 role, uint256 index) external view returns (address);

    /**
     * @dev Returns the number of accounts that have `role`. Can be used
     * together with {getRoleMember} to enumerate all bearers of a role.
     */
    function getRoleMemberCount(bytes32 role) external view returns (uint256);
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "./interface/IPermissions.sol";
import "../lib/Strings.sol";

/**
 *  @title   Permissions
 *  @dev     This contracts provides extending-contracts with role-based access control mechanisms
 */
contract Permissions is IPermissions {
    /// @dev Map from keccak256 hash of a role => a map from address => whether address has role.
    mapping(bytes32 => mapping(address => bool)) private _hasRole;

    /// @dev Map from keccak256 hash of a role to role admin. See {getRoleAdmin}.
    mapping(bytes32 => bytes32) private _getRoleAdmin;

    /// @dev Default admin role for all roles. Only accounts with this role can grant/revoke other roles.
    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;

    /// @dev Modifier that checks if an account has the specified role; reverts otherwise.
    modifier onlyRole(bytes32 role) {
        _checkRole(role, msg.sender);
        _;
    }

    /**
     *  @notice         Checks whether an account has a particular role.
     *  @dev            Returns `true` if `account` has been granted `role`.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account for which the role is being checked.
     */
    function hasRole(bytes32 role, address account) public view override returns (bool) {
        return _hasRole[role][account];
    }

    /**
     *  @notice         Checks whether an account has a particular role;
     *                  role restrictions can be swtiched on and off.
     *
     *  @dev            Returns `true` if `account` has been granted `role`.
     *                  Role restrictions can be swtiched on and off:
     *                      - If address(0) has ROLE, then the ROLE restrictions
     *                        don't apply.
     *                      - If address(0) does not have ROLE, then the ROLE
     *                        restrictions will apply.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account for which the role is being checked.
     */
    function hasRoleWithSwitch(bytes32 role, address account) public view returns (bool) {
        if (!_hasRole[role][address(0)]) {
            return _hasRole[role][account];
        }

        return true;
    }

    /**
     *  @notice         Returns the admin role that controls the specified role.
     *  @dev            See {grantRole} and {revokeRole}.
     *                  To change a role's admin, use {_setRoleAdmin}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     */
    function getRoleAdmin(bytes32 role) external view override returns (bytes32) {
        return _getRoleAdmin[role];
    }

    /**
     *  @notice         Grants a role to an account, if not previously granted.
     *  @dev            Caller must have admin role for the `role`.
     *                  Emits {RoleGranted Event}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account to which the role is being granted.
     */
    function grantRole(bytes32 role, address account) public virtual override {
        _checkRole(_getRoleAdmin[role], msg.sender);
        if (_hasRole[role][account]) {
            revert("Can only grant to non holders");
        }
        _setupRole(role, account);
    }

    /**
     *  @notice         Revokes role from an account.
     *  @dev            Caller must have admin role for the `role`.
     *                  Emits {RoleRevoked Event}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account from which the role is being revoked.
     */
    function revokeRole(bytes32 role, address account) public virtual override {
        _checkRole(_getRoleAdmin[role], msg.sender);
        _revokeRole(role, account);
    }

    /**
     *  @notice         Revokes role from the account.
     *  @dev            Caller must have the `role`, with caller being the same as `account`.
     *                  Emits {RoleRevoked Event}.
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param account  Address of the account from which the role is being revoked.
     */
    function renounceRole(bytes32 role, address account) public virtual override {
        if (msg.sender != account) {
            revert("Can only renounce for self");
        }
        _revokeRole(role, account);
    }

    /// @dev Sets `adminRole` as `role`'s admin role.
    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
        bytes32 previousAdminRole = _getRoleAdmin[role];
        _getRoleAdmin[role] = adminRole;
        emit RoleAdminChanged(role, previousAdminRole, adminRole);
    }

    /// @dev Sets up `role` for `account`
    function _setupRole(bytes32 role, address account) internal virtual {
        _hasRole[role][account] = true;
        emit RoleGranted(role, account, msg.sender);
    }

    /// @dev Revokes `role` from `account`
    function _revokeRole(bytes32 role, address account) internal virtual {
        _checkRole(role, account);
        delete _hasRole[role][account];
        emit RoleRevoked(role, account, msg.sender);
    }

    /// @dev Checks `role` for `account`. Reverts with a message including the required role.
    function _checkRole(bytes32 role, address account) internal view virtual {
        if (!_hasRole[role][account]) {
            revert(
                string(
                    abi.encodePacked(
                        "Permissions: account ",
                        Strings.toHexString(uint160(account), 20),
                        " is missing role ",
                        Strings.toHexString(uint256(role), 32)
                    )
                )
            );
        }
    }

    /// @dev Checks `role` for `account`. Reverts with a message including the required role.
    function _checkRoleWithSwitch(bytes32 role, address account) internal view virtual {
        if (!hasRoleWithSwitch(role, account)) {
            revert(
                string(
                    abi.encodePacked(
                        "Permissions: account ",
                        Strings.toHexString(uint160(account), 20),
                        " is missing role ",
                        Strings.toHexString(uint256(role), 32)
                    )
                )
            );
        }
    }
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

import "./interface/IPermissionsEnumerable.sol";
import "./Permissions.sol";

/**
 *  @title   PermissionsEnumerable
 *  @dev     This contracts provides extending-contracts with role-based access control mechanisms.
 *           Also provides interfaces to view all members with a given role, and total count of members.
 */
contract PermissionsEnumerable is IPermissionsEnumerable, Permissions {
    /**
     *  @notice A data structure to store data of members for a given role.
     *
     *  @param index    Current index in the list of accounts that have a role.
     *  @param members  map from index => address of account that has a role
     *  @param indexOf  map from address => index which the account has.
     */
    struct RoleMembers {
        uint256 index;
        mapping(uint256 => address) members;
        mapping(address => uint256) indexOf;
    }

    /// @dev map from keccak256 hash of a role to its members' data. See {RoleMembers}.
    mapping(bytes32 => RoleMembers) private roleMembers;

    /**
     *  @notice         Returns the role-member from a list of members for a role,
     *                  at a given index.
     *  @dev            Returns `member` who has `role`, at `index` of role-members list.
     *                  See struct {RoleMembers}, and mapping {roleMembers}
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *  @param index    Index in list of current members for the role.
     *
     *  @return member  Address of account that has `role`
     */
    function getRoleMember(bytes32 role, uint256 index) external view override returns (address member) {
        uint256 currentIndex = roleMembers[role].index;
        uint256 check;

        for (uint256 i = 0; i < currentIndex; i += 1) {
            if (roleMembers[role].members[i] != address(0)) {
                if (check == index) {
                    member = roleMembers[role].members[i];
                    return member;
                }
                check += 1;
            } else if (hasRole(role, address(0)) && i == roleMembers[role].indexOf[address(0)]) {
                check += 1;
            }
        }
    }

    /**
     *  @notice         Returns total number of accounts that have a role.
     *  @dev            Returns `count` of accounts that have `role`.
     *                  See struct {RoleMembers}, and mapping {roleMembers}
     *
     *  @param role     keccak256 hash of the role. e.g. keccak256("TRANSFER_ROLE")
     *
     *  @return count   Total number of accounts that have `role`
     */
    function getRoleMemberCount(bytes32 role) external view override returns (uint256 count) {
        uint256 currentIndex = roleMembers[role].index;

        for (uint256 i = 0; i < currentIndex; i += 1) {
            if (roleMembers[role].members[i] != address(0)) {
                count += 1;
            }
        }
        if (hasRole(role, address(0))) {
            count += 1;
        }
    }

    /// @dev Revokes `role` from `account`, and removes `account` from {roleMembers}
    ///      See {_removeMember}
    function _revokeRole(bytes32 role, address account) internal override {
        super._revokeRole(role, account);
        _removeMember(role, account);
    }

    /// @dev Grants `role` to `account`, and adds `account` to {roleMembers}
    ///      See {_addMember}
    function _setupRole(bytes32 role, address account) internal override {
        super._setupRole(role, account);
        _addMember(role, account);
    }

    /// @dev adds `account` to {roleMembers}, for `role`
    function _addMember(bytes32 role, address account) internal {
        uint256 idx = roleMembers[role].index;
        roleMembers[role].index += 1;

        roleMembers[role].members[idx] = account;
        roleMembers[role].indexOf[account] = idx;
    }

    /// @dev removes `account` from {roleMembers}, for `role`
    function _removeMember(bytes32 role, address account) internal {
        uint256 idx = roleMembers[role].indexOf[account];

        delete roleMembers[role].members[idx];
        delete roleMembers[role].indexOf[account];
    }
}

// SPDX-License-Identifier: Apache-2.0
pragma solidity ^0.8.0;

/// @author thirdweb

/**
 * @dev String operations.
 */
library Strings {
    bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        // Inspired by OraclizeAPI's implementation - MIT licence
        // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol

        if (value == 0) {
            return "0";
        }
        uint256 temp = value;
        uint256 digits;
        while (temp != 0) {
            digits++;
            temp /= 10;
        }
        bytes memory buffer = new bytes(digits);
        while (value != 0) {
            digits -= 1;
            buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
            value /= 10;
        }
        return string(buffer);
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        if (value == 0) {
            return "0x00";
        }
        uint256 temp = value;
        uint256 length = 0;
        while (temp != 0) {
            length++;
            temp >>= 8;
        }
        return toHexString(value, length);
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
     */
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
        bytes memory buffer = new bytes(2 * length + 2);
        buffer[0] = "0";
        buffer[1] = "x";
        for (uint256 i = 2 * length + 1; i > 1; --i) {
            buffer[i] = _HEX_SYMBOLS[value & 0xf];
            value >>= 4;
        }
        require(value == 0, "Strings: hex length insufficient");
        return string(buffer);
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is prefixed with "0x", encoded using 2 hexadecimal digits per byte,
    /// and the alphabets are capitalized conditionally according to
    /// https://eips.ethereum.org/EIPS/eip-55
    function toHexStringChecksummed(address value) internal pure returns (string memory str) {
        str = toHexString(value);
        /// @solidity memory-safe-assembly
        assembly {
            let mask := shl(6, div(not(0), 255)) // `0b010000000100000000 ...`
            let o := add(str, 0x22)
            let hashed := and(keccak256(o, 40), mul(34, mask)) // `0b10001000 ... `
            let t := shl(240, 136) // `0b10001000 << 240`
            for {
                let i := 0
            } 1 {

            } {
                mstore(add(i, i), mul(t, byte(i, hashed)))
                i := add(i, 1)
                if eq(i, 20) {
                    break
                }
            }
            mstore(o, xor(mload(o), shr(1, and(mload(0x00), and(mload(o), mask)))))
            o := add(o, 0x20)
            mstore(o, xor(mload(o), shr(1, and(mload(0x20), and(mload(o), mask)))))
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is prefixed with "0x" and encoded using 2 hexadecimal digits per byte.
    function toHexString(address value) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value);
        /// @solidity memory-safe-assembly
        assembly {
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(str, 0x3078) // Write the "0x" prefix.
            str := sub(str, 2) // Move the pointer.
            mstore(str, strLength) // Write the length.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is encoded using 2 hexadecimal digits per byte.
    function toHexStringNoPrefix(address value) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            str := mload(0x40)

            // Allocate the memory.
            // We need 0x20 bytes for the trailing zeros padding, 0x20 bytes for the length,
            // 0x02 bytes for the prefix, and 0x28 bytes for the digits.
            // The next multiple of 0x20 above (0x20 + 0x20 + 0x02 + 0x28) is 0x80.
            mstore(0x40, add(str, 0x80))

            // Store "0123456789abcdef" in scratch space.
            mstore(0x0f, 0x30313233343536373839616263646566)

            str := add(str, 2)
            mstore(str, 40)

            let o := add(str, 0x20)
            mstore(add(o, 40), 0)

            value := shl(96, value)

            // We write the string from rightmost digit to leftmost digit.
            // The following is essentially a do-while loop that also handles the zero case.
            for {
                let i := 0
            } 1 {

            } {
                let p := add(o, add(i, i))
                let temp := byte(i, value)
                mstore8(add(p, 1), mload(and(temp, 15)))
                mstore8(p, mload(shr(4, temp)))
                i := add(i, 1)
                if eq(i, 20) {
                    break
                }
            }
        }
    }

    /// @dev Returns the hex encoded string from the raw bytes.
    /// The output is encoded using 2 hexadecimal digits per byte.
    function toHexString(bytes memory raw) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(raw);
        /// @solidity memory-safe-assembly
        assembly {
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(str, 0x3078) // Write the "0x" prefix.
            str := sub(str, 2) // Move the pointer.
            mstore(str, strLength) // Write the length.
        }
    }

    /// @dev Returns the hex encoded string from the raw bytes.
    /// The output is encoded using 2 hexadecimal digits per byte.
    function toHexStringNoPrefix(bytes memory raw) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            let length := mload(raw)
            str := add(mload(0x40), 2) // Skip 2 bytes for the optional prefix.
            mstore(str, add(length, length)) // Store the length of the output.

            // Store "0123456789abcdef" in scratch space.
            mstore(0x0f, 0x30313233343536373839616263646566)

            let o := add(str, 0x20)
            let end := add(raw, length)

            for {

            } iszero(eq(raw, end)) {

            } {
                raw := add(raw, 1)
                mstore8(add(o, 1), mload(and(mload(raw), 15)))
                mstore8(o, mload(and(shr(4, mload(raw)), 15)))
                o := add(o, 2)
            }
            mstore(o, 0) // Zeroize the slot after the string.
            mstore(0x40, add(o, 0x20)) // Allocate the memory.
        }
    }
}

{
  "compilationTarget": {
    "contracts/Contract.sol": "InvisibleFriendsBurnContract"
  },
  "evmVersion": "london",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": true,
    "runs": 200
  },
  "remappings": []
}