import java.util.Scanner;

public class P05_AddAndSubtract {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int num1 = Integer.parseInt(scanner.nextLine());
        int num2 = Integer.parseInt(scanner.nextLine());
        int num3 = Integer.parseInt(scanner.nextLine());
        int sum1_2 = getSum(num1, num2);
        System.out.println(subtract(sum1_2, num3));

    }
    static int getSum(int num1, int num2) {

        return num1 + num2;
    }

    static int subtract(int sum, int num3) {
        return sum - num3;
    }
}