Solution.cpp

class Solution {
public:
    int numberOfGoodSubsets(vector<int>& nums) {
        int primes[10] = {2, 3, 5, 7, 11, 13, 17, 19, 23, 29};
        int cnt[31]{};
        for (int& x : nums) {
            ++cnt[x];
        }
        int n = 10;
        const int mod = 1e9 + 7;
        vector<long long> f(1 << n);
        f[0] = 1;
        for (int i = 0; i < cnt[1]; ++i) {
            f[0] = f[0] * 2 % mod;
        }
        for (int x = 2; x < 31; ++x) {
            if (cnt[x] == 0 || x % 4 == 0 || x % 9 == 0 || x % 25 == 0) {
                continue;
            }
            int mask = 0;
            for (int i = 0; i < n; ++i) {
                if (x % primes[i] == 0) {
                    mask |= 1 << i;
                }
            }
            for (int state = (1 << n) - 1; state; --state) {
                if ((state & mask) == mask) {
                    f[state] = (f[state] + 1LL * cnt[x] * f[state ^ mask]) % mod;
                }
            }
        }
        long long ans = 0;
        for (int i = 1; i < 1 << n; ++i) {
            ans = (ans + f[i]) % mod;
        }
        return ans;
    }
};