import java.util.*;
import java.io.*;

public class Main {
    public static void main(String[] args) throws Exception {
        
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out));
        
        String[] input = br.readLine().split(" ");
        int a = Integer.parseInt(input[0]);
        int b = Integer.parseInt(input[1]);
        int c = Integer.parseInt(input[2]);
        
        out.println(c - (a - b) >= 0 ? c - (a - b) : 0);
        out.close();
        
    }
}
/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