"use strict"
function main(arg) {
    var yokia = parseInt(arg.trim().split(" ")[0]);
    var yokib = parseInt(arg.trim().split(" ")[1]);
    var yokic = parseInt(arg.trim().split(" ")[2]);

    var kotae = 0;

    var hairumizu = yokia - yokib;
    kotae = yokic - hairumizu;
    
    if(kotae < 0){
        kotae = 0;
    }

    console.log(kotae);


}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));