leetcode-daily/cpp/2202/220222-CN.cpp

95 lines
2.4 KiB
C++

#include <vector>
#include <iostream>
class Solution {
private:
inline static const int primes[] = {2, 3, 5, 7, 11, 13, 17, 19, 23, 29};
inline static const int MOD = 1000000007;
public:
static int numberOfGoodSubsets(const std::vector<int>& nums) {
int cnt[31]{};
for (int i : nums)
++cnt[i];
// 2 x 3 = 6
// 2 x 5 = 10
// 2 x 7 = 14
// 2 x 11 = 22
// 2 x 13 = 26
// 3 x 5 = 15
// 3 x 7 = 21
long long ret = 0;
for (int i = 1; i < 1024; ++i) {
// Original numbers
long long now = 1;
for (int j = 0; j < 10; ++j)
if (i & (1 << j))
now = (now * cnt[primes[j]]) % MOD;
ret = (ret + now) % MOD;
if (i & 1) {
// 2-related numbers
for (int j = 1; j <= 5; ++j) {
if ((i & (1 << j)) && (now = cnt[primes[j] << 1])) {
// Now, there is no 2, no primes[j], but (primes[j] << 1).
for (int k = 1; k < 10; ++k)
if (k != j && (i & (1 << k)))
now = (now * cnt[primes[k]]) % MOD;
ret = (ret + now) % MOD;
}
}
}
if (i & 2) {
// 3-related numbers
// Only 5 (indexed 2) and 7 (indexed 3) is valid.
if ((i & 4) && (now = cnt[15])) {
for (int k = 0; k < 10; ++k)
if (k != 1 && k != 2 && (i & (1 << k)))
now = (now * cnt[primes[k]]) % MOD;
ret = (ret + now) % MOD;
}
if ((i & 8) && (now = cnt[21])) {
for (int k = 0; k < 10; ++k)
if (k != 1 && k != 3 && (i & (1 << k)))
now = (now * cnt[primes[k]]) % MOD;
ret = (ret + now) % MOD;
}
}
if ((now = cnt[30]) && ((i & 7) == 7)) {
// 2 * 3 * 5 == 30
for (int j = 3; j < 10; ++j)
if (i & (1 << j))
now = (now * cnt[primes[j]]) % MOD;
ret = (ret + now) % MOD;
}
// 2 - (11, 13) + 3 - (5, 7)
if (((i & 3) == 3) && (i & 61)) {
for (int j2 = 2; j2 <= 5; ++j2) {
for (int j3 = 2; j3 <= 3; ++j3) {
if (j2 != j3 && (i & (1 << j2)) && (i & (1 << j3))) {
now = (cnt[primes[j2] << 1] * cnt[primes[j3] * 3]) % MOD;
for (int k = 2; k < 10; ++k) {
if (k != j2 && k != j3 && (i & (1 << k))) {
now = (now * cnt[primes[k]]) % MOD;
}
}
ret = (ret + now) % MOD;
}
}
}
}
}
while (cnt[1]--) {
ret = (ret << 1) % MOD;
}
return ret % MOD;
}
};
int main() {
std::cout << Solution::numberOfGoodSubsets({5, 10, 1, 26, 24, 21, 24, 23, 11, 12, 27, 4, 17, 16, 2, 6, 1, 1, 6, 8, 13, 30, 24, 20, 2, 19});
return 0;
}