Leetcode 1994. The Number of Good Subsets

Count the subsets of nums whose product is a product of distinct primes (i.e., square-free with no repeated prime factors), modulo 1e9+7. With nums length up to 1e5 and values ≤30, the core challenge is using frequency compression and bitmask DP over the ≤10 primes ≤30 (treating 1s multiplicatively).