範例程式碼 uva993

//uva993
#include <cstdio>
#include <string>
#include <iostream>

using namespace std;

string solve(int n) {
    string ans = "";
    int i;

    while(n != 1) {
        for (i = 9; i > 1; i--) {
            if (n % i == 0) {
                n /= i;
                ans = (char)(i + '0') + ans;
                break;
            }
        }
        if (i == 1) return "-1";
    }
    return ans;
}


int main() {
    int test_case, n;
    string ans;

    scanf("%d", &test_case);

    while (test_case--) {
        scanf("%d", &n);

        if (n < 10) {
            printf("%d\n", n);
            continue;
        }
        cout << solve(n) << endl;
    }

    return 0;
}