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contracts...viewpure.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.8;

contract viewAndPureFunctions{
    uint public age;

    constructor(){
        age =20;
    }

    function fun1() public view returns(uint){
        return age;
    }
    function fun2() public pure returns(uint){
        return 1;
    }
    function fun3(uint _x) public pure returns(uint){
        return _x;
    }
    function fun4() public{
         age=age+100;
    }
    function fun5(uint _x,uint _y) public pure returns(uint){
        uint z = _x + _y;
        return z;
    }
}