#include <iostream>
#include <math.h>
#include <conio.h>
#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <string>
#include <cstring>
#include "stdio.h"
using namespace std;

char* sum(char *A, char *B, int dlin) {
    char *sum = new char[dlin];
    for (int i = dlin - 1; i >= 0; i--) {
        if (A[i] == '0' && B[i] == '0') {

        }
        if ((A[i] == '0' && B[i] == '1') || (A[i] == '1' && B[i] == '0')) {

        }
        if (A[i] == '1' && B[i] == '1') {
            if (A[i - 1] == '2') {

            }
        }
    }
    return sum;
}

int main() {
    SetConsoleOutputCP(1251);
    string l1, l2, sum;
    cout << "Введите два двоичных числа  в естественной форме:" << endl;
    getline(cin, l1);
    getline(cin, l2);

    int dl1 = l1.length();
    int dl2 = l2.length();
    int dif;
    dif = dl1 - dl2;
    if (dif > 0) {
        while (dif > 0) {
            l2 = '0' + l2;
            dif--;
        }
    }
    if (dif < 0) {
        while (abs(dif) > 0) {
            dif = abs(dif);
            l1 = '0' + l1;
            dif--;
        }

    }
    dl1 = l1.length();
    while (dl1 >= 0) {

        switch (l1[dl1 - 1]) {

        case '0':
            if (l2[dl1] == '0') {
                sum = '0' + sum;
            }
            else
                sum = '1' + sum;
        case '1':
            if (l2[dl1] == '0') {
                sum = '1' + sum;
            }
            else {
                sum = '0' + sum;
                if (dl1 > 0) {
                    if (l1[dl1 - 1] == '1') {
                        l1[dl1 - 1] = '2';
                    }
                    else
                        l1[dl1 - 1] = '1';
                }
                else
                    sum = '1' + sum;

            }
        case '2':
            if (l2[dl1] == '0') {
                sum = '0' + sum;
                if (dl1 > 0) {
                    if (l1[dl1 - 1] == '1') {
                        l1[dl1 - 1] = '2';
                    }
                    else
                        l1[dl1 - 1] = '1';

                }
                else
                    sum = '1' + sum;
            }
            else {
                sum = '1' + sum;
                if (dl1 > 0) {
                    if (l1[dl1 - 1] == '1') {
                        l1[dl1 - 1] = '2';
                    }
                    else
                        l1[dl1 - 1] = '1';
                }
                else
                    sum = '1' + sum;

            }
        }
        dl1--;
    }

    /* if (dl1 != dl2) {
     if (dl1 > dl2) {
     while (dl1 != dl2) {
     dl2++;
     for (int i = dl2 - 1; i >= 0; i--) {
     cisl2[dl2] = '\0';
     char tmp = cisl2[i];
     cisl2[i + 1] = tmp;
     }
     cisl2[0] = '0';
     }
     }
     else
     while (dl1 != dl2) {
     dl1++;
     for (int i = dl1 - 1; i >= 0; i--) {
     cisl1[dl1] = '\0';
     char tmp = cisl1[i];
     cisl1[i + 1] = tmp;
     }
     cisl1[0] = '0';
     }

     } */
    // dl1 = dl2;
    /* if (cisl1[0] == '1') {
     for (int i = 0; i < dl1; i++) {
     if (cisl1[i] == '1') {
     cisl1[i] = '0';
     }
     else
     cisl1[i] = '1';
     }
     }
     if (cisl2[0] == '1') {
     for (int i = 0; i < dl1; i++) {
     if (cisl2[i] == '1') {
     cisl2[i] = '0';
     }
     else
     cisl2[i] = '1';
     }
     } */
    /* cout << l1 << endl;
     cout << l2; */
    cout << sum;
    getch();
    return 0;
}