제출 #781208

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
781208		NK_	Ice Hockey World Championship (CEOI15_bobek)	C++17	100 / 100	166 ms	16724 KiB

bobek

// Success consists of going from failure to failure without loss of enthusiasm
#include <bits/stdc++.h>

using namespace std;

#define nl '\n'
#define sz(x) int(x.size())

using ll = long long;

template<class T> using V = vector<T>;

int main() {
	cin.tie(0)->sync_with_stdio(0);
	
	int N; ll M; cin >> N >> M;

	int a = N / 2, b = N - a;

	V<ll> A(a), B(b);
	for(auto& x : A) cin >> x;
	for(auto& x : B) cin >> x;

	V<ll> SA, SB;
	auto get = [&](const V<ll>& X) {
		int n = sz(X);
		V<ll> S(1 << n, 0);
		for(int i = 1; i < (1<<n); i++) {
			int low = i & -i;
			S[i] = S[i ^ low] + X[__lg(low)];
			if (S[i ^ low] == -1 || S[i] > M) S[i] = -1;
		}
		sort(rbegin(S), rend(S));
		while(S.back() == -1) S.pop_back();

		// for(auto x : S) cout << x << " ";
		// cout << endl;

		return S;
	};	

	SA = get(A);
	SB = get(B);

	ll ans = 0;
	int r = sz(SB) - 1;
	for(auto x : SA) {
		ll left = M - x;
		while(r >= 0 && SB[r] <= left) {
			// cout << SB[r] << endl;
			r--;
		}
		// cout << left << " " << r << endl;
		ans += sz(SB) - 1 - r;
	}

	cout << ans << nl;

    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10