import java.util.*;

public class Main{
    public static void main(String[] args){
        Scanner scan = new java.util.Scanner(System.in);
        int a = scan.nextInt();
        int b = scan.nextInt();
        int c = scan.nextInt();
        if(b + c <= a){
            System.out.println("0");
        }else{
            System.out.println(b + c - a);
        }
    }
} import java.util.*; util.* java public class Main{
    public static void main(String[] args){
        Scanner scan = new java.util.Scanner(System.in);
        int a = scan.nextInt();
        int b = scan.nextInt();
        int c = scan.nextInt();
        if(b + c <= a){
            System.out.println("0");
        }else{
            System.out.println(b + c - a);
        }
    }
} Main public static void main(String[] args){
        Scanner scan = new java.util.Scanner(System.in);
        int a = scan.nextInt();
        int b = scan.nextInt();
        int c = scan.nextInt();
        if(b + c <= a){
            System.out.println("0");
        }else{
            System.out.println(b + c - a);
        }
    } main {
        Scanner scan = new java.util.Scanner(System.in);
        int a = scan.nextInt();
        int b = scan.nextInt();
        int c = scan.nextInt();
        if(b + c <= a){
            System.out.println("0");
        }else{
            System.out.println(b + c - a);
        }
    } Scanner scan = new java.util.Scanner(System.in); scan new java.util.Scanner(System.in) int a = scan.nextInt(); a scan.nextInt() scan.nextInt scan int b = scan.nextInt(); b scan.nextInt() scan.nextInt scan int c = scan.nextInt(); c scan.nextInt() scan.nextInt scan if(b + c <= a){
            System.out.println("0");
        }else{
            System.out.println(b + c - a);
        } b + c <= a b + c b c a {
            System.out.println("0");
        } System.out.println("0") System.out.println System.out System System.out "0" {
            System.out.println(b + c - a);
        } System.out.println(b + c - a) System.out.println System.out System System.out b + c - a b + c b c a String[] args args public class Main{
    public static void main(String[] args){
        Scanner scan = new java.util.Scanner(System.in);
        int a = scan.nextInt();
        int b = scan.nextInt();
        int c = scan.nextInt();
        if(b + c <= a){
            System.out.println("0");
        }else{
            System.out.println(b + c - a);
        }
    }
} public class Main{
    public static void main(String[] args){
        Scanner scan = new java.util.Scanner(System.in);
        int a = scan.nextInt();
        int b = scan.nextInt();
        int c = scan.nextInt();
        if(b + c <= a){
            System.out.println("0");
        }else{
            System.out.println(b + c - a);
        }
    }
} Main
import java.util.*;

public class Main{
    public static void main(String[] args){
        Scanner scan = new java.util.Scanner(System.in);
        int a = scan.nextInt();
        int b = scan.nextInt();
        int c = scan.nextInt();
        if(b + c <= a){
            System.out.println("0");
        }else{
            System.out.println(b + c - a);
        }
    }
}