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

public class Main {

    private static Scanner in = new Scanner(System.in);
    private static PrintWriter out = new PrintWriter(System.out);

    private static final long MOD = (long) 1e9 + 7;

    public static void main(String[] args) {
        solve();
        out.flush();
    }

    private static void solve() {
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();

        out.println(a - b >= c ? 0 : c - (a - b));
    }

} import java.io.PrintWriter; PrintWriter java.io import java.util.Scanner; Scanner java.util public class Main {

    private static Scanner in = new Scanner(System.in);
    private static PrintWriter out = new PrintWriter(System.out);

    private static final long MOD = (long) 1e9 + 7;

    public static void main(String[] args) {
        solve();
        out.flush();
    }

    private static void solve() {
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();

        out.println(a - b >= c ? 0 : c - (a - b));
    }

} Main private static Scanner in = new Scanner(System.in); in new Scanner(System.in) private static PrintWriter out = new PrintWriter(System.out); out new PrintWriter(System.out) private static final long MOD = (long) 1e9 + 7; MOD (long) 1e9 + 7 (long) 1e9 7 public static void main(String[] args) {
        solve();
        out.flush();
    } main {
        solve();
        out.flush();
    } solve() solve out.flush() out.flush out String[] args args private static void solve() {
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();

        out.println(a - b >= c ? 0 : c - (a - b));
    } solve {
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();

        out.println(a - b >= c ? 0 : c - (a - b));
    } int a = in.nextInt(); a in.nextInt() in.nextInt in int b = in.nextInt(); b in.nextInt() in.nextInt in int c = in.nextInt(); c in.nextInt() in.nextInt in out.println(a - b >= c ? 0 : c - (a - b)) out.println out a - b >= c ? 0 : c - (a - b) a - b >= c a - b a b c 0 c - (a - b) c (a - b) a b public class Main {

    private static Scanner in = new Scanner(System.in);
    private static PrintWriter out = new PrintWriter(System.out);

    private static final long MOD = (long) 1e9 + 7;

    public static void main(String[] args) {
        solve();
        out.flush();
    }

    private static void solve() {
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();

        out.println(a - b >= c ? 0 : c - (a - b));
    }

} public class Main {

    private static Scanner in = new Scanner(System.in);
    private static PrintWriter out = new PrintWriter(System.out);

    private static final long MOD = (long) 1e9 + 7;

    public static void main(String[] args) {
        solve();
        out.flush();
    }

    private static void solve() {
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();

        out.println(a - b >= c ? 0 : c - (a - b));
    }

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

public class Main {

    private static Scanner in = new Scanner(System.in);
    private static PrintWriter out = new PrintWriter(System.out);

    private static final long MOD = (long) 1e9 + 7;

    public static void main(String[] args) {
        solve();
        out.flush();
    }

    private static void solve() {
        int a = in.nextInt();
        int b = in.nextInt();
        int c = in.nextInt();

        out.println(a - b >= c ? 0 : c - (a - b));
    }

}
