function processData(input) {
    //Enter your code here
    var inp = input.split(" ").map(Number);
    
    var BigNum = require("bignumber.js");
    BigNum.config({ EXPONENTIAL_AT: 20 });
    
    var a = inp[0];
    var b = inp[1];
    var t = inp[2];
    var ab = 0.5*(a + b);
    
    var y = new BigNum('1e+9',10);
    y = y.add(7);
    
    
    var virNumTi = new BigNum(ab,10);
    
    
    virNumTi = virNumTi.toPower(t);
    virNumTi = virNumTi.mod(y);
    
    console.log(virNumTi.toString());
    
    
    
} 

process.stdin.resume();
process.stdin.setEncoding("ascii");
_input = "";
process.stdin.on("data", function (input) {
    _input += input;
});

process.stdin.on("end", function () {
   processData(_input);
});