import java.util.Scanner;

public class Main {
  public static void main (String[] args) {
    Scanner in = new Scanner(System.in);

    while (in.hasNext()) {
      int A = in.nextInt();
      int B = in.nextInt();
      int C = in.nextInt();

      if (A - B >= C) {
        System.out.println(0);
      } else {
        System.out.println(C - (A - B));
      }
    }
  }
} import java.util.Scanner; Scanner java.util public class Main {
  public static void main (String[] args) {
    Scanner in = new Scanner(System.in);

    while (in.hasNext()) {
      int A = in.nextInt();
      int B = in.nextInt();
      int C = in.nextInt();

      if (A - B >= C) {
        System.out.println(0);
      } else {
        System.out.println(C - (A - B));
      }
    }
  }
} Main public static void main (String[] args) {
    Scanner in = new Scanner(System.in);

    while (in.hasNext()) {
      int A = in.nextInt();
      int B = in.nextInt();
      int C = in.nextInt();

      if (A - B >= C) {
        System.out.println(0);
      } else {
        System.out.println(C - (A - B));
      }
    }
  } main {
    Scanner in = new Scanner(System.in);

    while (in.hasNext()) {
      int A = in.nextInt();
      int B = in.nextInt();
      int C = in.nextInt();

      if (A - B >= C) {
        System.out.println(0);
      } else {
        System.out.println(C - (A - B));
      }
    }
  } Scanner in = new Scanner(System.in); in new Scanner(System.in) while (in.hasNext()) {
      int A = in.nextInt();
      int B = in.nextInt();
      int C = in.nextInt();

      if (A - B >= C) {
        System.out.println(0);
      } else {
        System.out.println(C - (A - B));
      }
    } in.hasNext() in.hasNext in {
      int A = in.nextInt();
      int B = in.nextInt();
      int C = in.nextInt();

      if (A - B >= C) {
        System.out.println(0);
      } else {
        System.out.println(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 if (A - B >= C) {
        System.out.println(0);
      } else {
        System.out.println(C - (A - B));
      } A - B >= C A - B A B C {
        System.out.println(0);
      } System.out.println(0) System.out.println System.out System System.out 0 {
        System.out.println(C - (A - B));
      } System.out.println(C - (A - B)) System.out.println System.out System System.out C - (A - B) C (A - B) A B String[] args args public class Main {
  public static void main (String[] args) {
    Scanner in = new Scanner(System.in);

    while (in.hasNext()) {
      int A = in.nextInt();
      int B = in.nextInt();
      int C = in.nextInt();

      if (A - B >= C) {
        System.out.println(0);
      } else {
        System.out.println(C - (A - B));
      }
    }
  }
} public class Main {
  public static void main (String[] args) {
    Scanner in = new Scanner(System.in);

    while (in.hasNext()) {
      int A = in.nextInt();
      int B = in.nextInt();
      int C = in.nextInt();

      if (A - B >= C) {
        System.out.println(0);
      } else {
        System.out.println(C - (A - B));
      }
    }
  }
} Main
import java.util.Scanner;

public class Main {
  public static void main (String[] args) {
    Scanner in = new Scanner(System.in);

    while (in.hasNext()) {
      int A = in.nextInt();
      int B = in.nextInt();
      int C = in.nextInt();

      if (A - B >= C) {
        System.out.println(0);
      } else {
        System.out.println(C - (A - B));
      }
    }
  }
}