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contracts...overridefunctionInMultipleInheritance.sol

//SPDX-License-Identifier: MIT
pragma solidity ^0.8;

contract A{
    uint public a;
    constructor(){
        a = 100;
    }

    function funA() public{
        a = 10;
    }
    //to this function override in derived class use virtual keyword in it
    function func() public pure virtual returns(string memory){
        return "this is func A";
    }
}

contract B is A{
    uint public b;
    constructor(){
        b =200;
        a = 777;
    }
    function funB() public{
        b =20;
    }
    function func() public pure virtual override returns(string memory){
        return "this is func B";
    }
}
contract C is A,B{
    function func() public pure override(A,B) returns(string memory){
        return "this is function in contract c";
    }
 }