Super Ugly Number

Write a program to find the nth super ugly number.

Super ugly numbers are positive numbers whose all prime factors are in the given prime list primes of size k. For example, [1, 2, 4, 7, 8, 13, 14, 16, 19, 26, 28, 32] is the sequence of the first 12 super ugly numbers given primes = [2, 7, 13, 19] of size 4.

Note:
(1) 1 is a super ugly number for any given primes.
(2) The given numbers in primes are in ascending order.
(3) 0 < k ≤ 100, 0 < n ≤ 10^6, 0 < primes[i] < 1000.

类似Ugly number二,创建长度为n的数组,依次生成n个ugly number。代码如下:
public class Solution {
    public int nthSuperUglyNumber(int n, int[] primes) {
        int[] count = new int[primes.length];
        int[] result = new int[n];
        result[0] = 1;
        int index = 1;
        while(index < n) {
            int min = Integer.MAX_VALUE;
            for(int i = 0; i < count.length; i++) {
                if(min > result[count[i]] * primes[i]) 
                    min = result[count[i]] * primes[i];
            }
            result[index ++] = min;
            for(int i = 0; i < count.length; i++) {
                if(min == result[count[i]] * primes[i]) count[i] ++;
            }
        }
        return result[n - 1];
    }
}

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