import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String inputStr[] = scanner.nextLine().split(" ");
        int a = Integer.valueOf(inputStr[0]);
        int b = Integer.valueOf(inputStr[1]);
        int c = Integer.valueOf(inputStr[2]);
        int ans = c - (a - b);
        System.out.println(ans < 0? 0: ans);
    }
}
/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