import java.util.Scanner;

public class Main { 

	public static void main(String[] args) {
    	Scanner sc = new Scanner(System.in);
    	String[] line = sc.nextLine().split(" ");
    	int intA = Integer.parseInt(line[0]);
    	int intB = Integer.parseInt(line[1]);
    	int intC = Integer.parseInt(line[2]);
    	int tmp1 = intA - intB;
    	int tmp2 = intC - tmp1;
    	int result = 0;
    	if(tmp2 < 0) {
    		result = 0;
    	}else {
    		result = tmp2;
    	}
    	

    	System.out.println(result);
    	
	}
}
/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