string s1, s2;
    cin >> s1 >> s2;
    int n = s1.length(), m = s2.length();
    int *arr1 = new int[n];
    int *arr2 = new int[m];
    for (int i = 0; i < n; i++) {
        arr1[i] = s1[i] - 48;
    }
    for (int i = 0; i < m; i++) {
        arr2[i] = s2[i] - 48;
    }
    int i = 0; int j = 0;
    for (int k = 0; k < m + n - 1; ++k) {
        if (i < n && j < m) {
            if (arr1[i] < arr2[j]) {
                cout << arr1[i];
                ++i;
            }
            else {
                cout << arr2[j];
                ++j;
            }
        } else {
             if (i >= n && j < m) {
                 while (j < m) {
                     cout << arr2[j];
                     ++j;
                 }
             }
             if (j >= m && i < n) {
                 while (i < n) {
                     cout << arr1[i];
                     ++i;
                 }
             }
        }
    }