import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
    	Scanner sc = new Scanner(System.in);
        String line = sc.nextLine();
        String[] strArray = line.split(" ");
        int A = Integer.parseInt(strArray[0]);
        int B = Integer.parseInt(strArray[1]);
        int C = Integer.parseInt(strArray[2]);
        
        int capacity = A - B;
        int result = (C > capacity) ? C - capacity : 0;
        
        System.out.println(result);
    }



} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
    	Scanner sc = new Scanner(System.in);
        String line = sc.nextLine();
        String[] strArray = line.split(" ");
        int A = Integer.parseInt(strArray[0]);
        int B = Integer.parseInt(strArray[1]);
        int C = Integer.parseInt(strArray[2]);
        
        int capacity = A - B;
        int result = (C > capacity) ? C - capacity : 0;
        
        System.out.println(result);
    }



} Main public static void main(String[] args) {
    	Scanner sc = new Scanner(System.in);
        String line = sc.nextLine();
        String[] strArray = line.split(" ");
        int A = Integer.parseInt(strArray[0]);
        int B = Integer.parseInt(strArray[1]);
        int C = Integer.parseInt(strArray[2]);
        
        int capacity = A - B;
        int result = (C > capacity) ? C - capacity : 0;
        
        System.out.println(result);
    } main {
    	Scanner sc = new Scanner(System.in);
        String line = sc.nextLine();
        String[] strArray = line.split(" ");
        int A = Integer.parseInt(strArray[0]);
        int B = Integer.parseInt(strArray[1]);
        int C = Integer.parseInt(strArray[2]);
        
        int capacity = A - B;
        int result = (C > capacity) ? C - capacity : 0;
        
        System.out.println(result);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String line = sc.nextLine(); line sc.nextLine() sc.nextLine sc String[] strArray = line.split(" "); strArray line.split(" ") line.split line " " int A = Integer.parseInt(strArray[0]); A Integer.parseInt(strArray[0]) Integer.parseInt Integer strArray[0] strArray 0 int B = Integer.parseInt(strArray[1]); B Integer.parseInt(strArray[1]) Integer.parseInt Integer strArray[1] strArray 1 int C = Integer.parseInt(strArray[2]); C Integer.parseInt(strArray[2]) Integer.parseInt Integer strArray[2] strArray 2 int capacity = A - B; capacity A - B A B int result = (C > capacity) ? C - capacity : 0; result (C > capacity) ? C - capacity : 0 (C > capacity) C capacity C - capacity C capacity 0 System.out.println(result) System.out.println System.out System System.out result String[] args args public class Main {
    public static void main(String[] args) {
    	Scanner sc = new Scanner(System.in);
        String line = sc.nextLine();
        String[] strArray = line.split(" ");
        int A = Integer.parseInt(strArray[0]);
        int B = Integer.parseInt(strArray[1]);
        int C = Integer.parseInt(strArray[2]);
        
        int capacity = A - B;
        int result = (C > capacity) ? C - capacity : 0;
        
        System.out.println(result);
    }



} public class Main {
    public static void main(String[] args) {
    	Scanner sc = new Scanner(System.in);
        String line = sc.nextLine();
        String[] strArray = line.split(" ");
        int A = Integer.parseInt(strArray[0]);
        int B = Integer.parseInt(strArray[1]);
        int C = Integer.parseInt(strArray[2]);
        
        int capacity = A - B;
        int result = (C > capacity) ? C - capacity : 0;
        
        System.out.println(result);
    }



} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
    	Scanner sc = new Scanner(System.in);
        String line = sc.nextLine();
        String[] strArray = line.split(" ");
        int A = Integer.parseInt(strArray[0]);
        int B = Integer.parseInt(strArray[1]);
        int C = Integer.parseInt(strArray[2]);
        
        int capacity = A - B;
        int result = (C > capacity) ? C - capacity : 0;
        
        System.out.println(result);
    }



}