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contracts...statevariable.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.8;

contract stateVariable{
    //state variable which is defined in contract but used outside of the functions
    //state variable stored on blockchain block storage so we can't create extra state variable bcz its cost gas
    uint public salary;
    
    constructor(){
        salary = 10;
    }

    function setSalary(uint _salary) public{
        salary = _salary;
    }
}