import java.io.PrintWriter;
import java.util.Scanner;

public class Main{

	public static void main(String[] args){
		//入力
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		sc.close();

		//処理
		int ans = Math.max(c - a + b, 0);
		
		//出力
		PrintWriter out = new PrintWriter(System.out);
		out.println(ans);
		out.flush();
	}
}
/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