Submission #477353

#	Time	Username	Problem	Language	Result	Execution time	Memory
477353		BThero	Cards (LMIO19_korteles)	C++17	36 / 100	1098 ms	67548 KiB

korteles

#include <bits/stdc++.h>

#define pb push_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()

using namespace std;

typedef long long ll;

const int MAXN = (int)5e5 + 5;

unordered_map<ll, int> cnt[16];
array<int, 4> arr[MAXN];
int n;

int encode(char a, char b) {
	return (a - 'A') * 26 + (b - 'A');
}

bool bit(int x, int p) {
	return x & (1 << p);
}

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
	cin >> n;

	for (int i = 0; i < n; i++) {
		string x, y;
		cin >> x >> y;
		arr[i][0] = encode(x[0], x[1]);
		arr[i][1] = encode(x[0], y[0]);
		arr[i][2] = encode(x[1], y[1]);
		arr[i][3] = encode(y[0], y[1]);
	}

	ll ans = 0;

	for (int i = 0; i < n; i++) {
		for (int mask = 1; mask < 16; mask++) {
			ll cur = 0;

			for (int j = 0; j < 4; j++) {
				if (bit(mask, j)) {
					cur = cur * 26 * 26 + arr[i][j];
				}
			}

			int pp = __builtin_popcount(mask);
			auto it = cnt[mask].find(cur);
			ll tmp = (it == cnt[mask].end() ? 0 : it -> second);

			if (pp % 2 == 1) {
				ans += tmp;
			}
			else {
				ans -= tmp;
			}
		}

		reverse(all(arr[i]));

		for (int mask = 1; mask < 16; mask++) {
			ll cur = 0;

			for (int j = 0; j < 4; j++) {
				if (bit(mask, j)) {
					cur = cur * 26 * 26 + arr[i][j];
				}
			}

			cnt[mask][cur]++;
		}
	}

	cout << ans << '\n';
	return 0;
}

• Subtask 1: 16 / 16
• Subtask 2: 20 / 20
• Subtask 3: 0 / 20
• Subtask 4: 0 / 19
• Subtask 5: 0 / 25