#include <iostream>
#include <cmath>

using namespace std;

int enter(int max, int min) {
    int temp = 0;
    bool iscorrect;
    do {
        cin >> temp;
        if ((temp > min) && (temp < max)) {
            iscorrect = false;
        } else {
            cout << "This is a mistake. Please enter again!\n";
            iscorrect = true;
        }
    } while (iscorrect);
    return temp;
}

int transfer(int j, int n, int num) {
    int res = 0;
    int temp = 1;
    for (int i = j; i < n - 1; i++) {
        temp = temp * 10;
    }
    res = res + (num * temp);
    return res;
}

int subtraction(int j, int n, int num) {
    int res = 0;
    int temp = 1;
    temp = temp * 10;
    res = res + (num % temp);
    return res;
}

int main() {
    int n;
    int num1 = 0;
    int num2 = 0;
    int numb1[10];
    int numb2[10];
    int res[10];
    cout << "Enter the number of numb (n > 0 and n < 10)\n";
    n = enter(10, 0);
    for (int i = 0; i < n; i++) {
        cout << "Enter the " << i + 1 << " digit of the first number(digit > 0 and digit < 10)\n";
        numb1[i] = enter(10, -1);
    }
    for (int i = 0; i < n; i++) {
        cout << "Enter the " << i + 1 << " digit of the second number(digit > 0 and digit < 10)\n";
        numb2[i] = enter(10, -1);
    }
    for (int i = n - 1; i > -1; i--) {
        num1 = num1 + transfer(i, n, numb1[i]);
        num2 = num2 + transfer(i, n, numb2[i]);
    }
    num1 = num1 - num2;
    if (num1 < 0) {
        num1 = abs(num1);
        for (int i = n - 1; i > -1; i--) {
            res[i] = subtraction(i, n, num1);
            num1 = num1 / 10;
        }
        res[0] = res[0] * (-1);
    } else {
        for (int i = n - 1; i > -1; i--) {
            res[i] = subtraction(i, n, num1);
            num1 = num1 / 10;
        }
    }
    for (int i = 0; i < n; i++) {
        cout << res[i];
    }
    return 0;
}