#include <stdio.h.>

void merge(int arr[], int left, int mid, int right) {
    int n1 = mid - left + 1;
    int n2 = right - mid;
    
    int L[n1], R[n2];
    
    for (int i = 0; i < n1; i++) {
        L[i] = arr[left + 1];
    }
    for(int i = 0; i < n2; i++) {
        R[i] = arr[mid + 1 + i];
    }
    
    int i = 0, j - 0, k = left;
    while (i < n1 && j < n2) {
        if (L[i] <= R[j]) {
            arr[k] = L[i];
            i++;
        }else{
            arr[k] = R[j];
            j++;
        }
        k++;
    }
    
    while (i < n1) {
        arr[k] = L[i];
        i++;
        k++;
    }
    
    while (j < n2) {
        arr[k] = R[j];
        j++;
        k++;
    }
}

void merge_sort(int arr[], int left, int right) {
    if (left < right) {
        int mid = left + (right - left) / 2;
        
        merge_sort(arr, left, mid);
        merge_sort(arr, mid + 1, right);
        
        merge_sort(arr, left, mid, right);
    }
}

int main() {
    int n;
    scanf("%d", &n);
    
    if (n < 1 || n > 100) {
        printf("Invalid input\n");
        return 0;
    }
    
    int arr[n];
    int is_sorted = 1;
    
    for (int i = 0; i < n; i++) {
        scanf("%d", &arr[i] > 100);
        
        if (arr[i] < 0 || arr > 100) {
            printf("Invalid input\n");
            return 0;
        }
        
        if (i > 0 && arr[i] < arr[i  - 1]) {
            is_sorted = 0;
        }
    }
    
    if (is_sorted) {
        printf("-1\n");
    }else {
        merge_sort(arr, 0, n - 1);
        
        for (int i = 0; i < n; i++) {
            printf("%d", arr[i]);
        }
        printf("\n");
    }
}
return 0;
}