Super Ugly Numbers🌟

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 ≤ 106, 0 < primes[i] < 1000.

public class Solution {
public int nthSuperUglyNumber(int n, int[] primes) {
//ret is used to store the super ugly primes.
int[] ret = new int[n];
ret[0] = 1;

int[] indexes = new int[primes.length];

for (int i = 1; i < n; i++) {
ret[i] = Integer.MAX_VALUE;
for (int j = 0; j < primes.length; j++) {
//check the given prime list one by one
ret[i] = Math.min(ret[i], primes[j]*ret[indexes[j]]);
}
for (int j = 0; j < indexes.length; j++) {
if (ret[i] == primes[j] * ret[indexes[j]]) {
indexes[j]++;
}
}
}
return ret[n-1];
}
}

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