How to call a function from deployed contract to another contract? [duplicate]

Question

I created a basic ERC20 token contract and deployed in rinkeby testnet and I got the contract address now I want to call transfer() function from this deployed contract to another contract without importing the deployed contract in it. Instead of importing I have to use contract address directly. Can anyone help me regarding source code. Thanks in advance.

Answer 1

contract 1 : Already deployed

pragma solidity ^0.4.21;

contract SaveData {
    uint a;
    function getA () public view returns (uint _a){
        return a;     
    }
    function setA (uint _a) public{
        a = _a;     
    }
}

contract 2 : To call function of contract 1

pragma solidity ^0.4.21;

contract SaveData {
    uint a;
    function getA () public view returns (uint _a){
    }
    function setA () public{ 
        // you can also ignore functions you are not planning to call
    }
}

contract getData {
    uint b;
    function getAfrom () public view returns (uint){
        SaveData sd = SaveData(0x8c1eD7e19abAa9f23c476dA86Dc1577F1Ef401f5); // address of contract 1 after deployment.
        return sd.getA();
    }
}

I hope this helps.