摘要：
// SPDX-License-Identifier: GPL-3.0 pragma solidity ^0.8.7; //remove array element by shifting elements to left //[1,2,3,4,5,6] -- remove(2) --> [1,2, 阅读全文
摘要：
// SPDX-License-Identifier: GPL-3.0 pragma solidity ^0.8.7; //mapping //how to declare a mapping (simple and nested) //Set, get ,delete //["alice", "b 阅读全文