UVA - 993 - Product of digits （简单贪心）

993 Product of digits

For a given non-negative integer number N, ?nd the minimal natural Q such that the product of all

Input

subsequent line contains one data set which consists of one non-negative integer number N (0 ≤ N ≤109).

Output

Sample Input

Sample Output

思路：找N的9 ~ 2的因数（按降序找）的个数，输出按升序

AC代码：

#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <iostream>
using namespace std;

int T, N;
int a[10];

int main() {
	scanf("%d", &T);
	while(T--) {
		scanf("%d", &N);
		if(N == 1) {
			printf("1\n");
			continue;
		}
		memset(a, 0, sizeof(a));
		for(int i = 9; i >= 2; i--) {
			if(N == 1) break;
			while(N % i == 0) {
				a[i] ++;
				N /= i;
			}
		}
		if(N != 1) {
			printf("-1\n");
			continue;
		}
		for(int i = 2; i < 10; i++) {
			while(a[i] != 0) {
				printf("%d", i);
				a[i] --;
			}
		}
		printf("\n");
	}
	return 0;
}