import java.util.Scanner;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner scan = new Scanner(System.in);
        int A = Integer.parseInt(scan.next()); 
        int B = Integer.parseInt(scan.next());
        int C = Integer.parseInt(scan.next());
        scan.close();
        
        int res = C - (A - B);
        res = res < 0 ? 0 : res;
        System.out.println(res);
    }
}
/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