import java.util.*;

class Main {

    static int solve(int a, int b, int c) {
        int re =  c - (a-b);
        return re>0?re:0;
    }

    public static void main(String[] as) {
        Scanner stdIn=new Scanner(System.in);
        int a=stdIn.nextInt();
        int b=stdIn.nextInt();
        int c=stdIn.nextInt();

        System.out.println(solve(a,b,c));
    }

}



/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz