LeetCode 313.

package lc_313;

import java.util.*;

/**
 * evolution from LC-264 Ugly Number II
 */
public class Solution {
    public int nthSuperUglyNumber(int n, int[] primes) {
        int[] ugly = new int[n];
        ugly[0] = 1;

        int[] index = new int[primes.length];
        int[] factors = Arrays.copyOf(primes, primes.length);
        int min = Integer.MAX_VALUE, tmp = 0;
        List<Integer> min_p = new ArrayList<>();

        for (int i=1; i<n; i++){
            for (int j=0; j<primes.length; j++){
                if (factors[j] == min){
                    min_p.add(j);
                }
                if (factors[j] > 0 && factors[j] < min){
                    min_p.clear();
                    min = factors[j];
                    min_p.add(j);
                }
            }
            ugly[i] = min;
            while (!min_p.isEmpty()){
                tmp = min_p.remove(0);
                factors[tmp] = primes[tmp] * ugly[++index[tmp]];
            }
            min = Integer.MAX_VALUE;
        }
        return ugly[n - 1];
    }
}