import java.util.Scanner;

public class Main {

    public static void main(String[] args) {

        Scanner scan = new Scanner(System.in);
        int a = scan.nextInt();
        int b = scan.nextInt();
        int c = scan.nextInt();

        int nowA = a - b;

        int nowc = c - nowA;

        if ( nowc < 0) {
            System.out.print(0);
        }else {
            System.out.print(nowc);
        }

    }


}


/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