Submission #227134

#	Time	Username	Problem	Language	Result	Execution time	Memory
227134		maruii	Collecting Stamps 3 (JOI20_ho_t3)	C++14	100 / 100	74 ms	66040 KiB

ho_t3

#include <bits/stdc++.h>
using namespace std;

int N, L, X[205], T[205], D[205][205][205][2], ans;

int main() {
	ios_base::sync_with_stdio(0), cin.tie(0);
	cin >> N >> L;
	for (int i = 1; i <= N; ++i) cin >> X[i];
	for (int i = 1; i <= N; ++i) cin >> T[i];
	for (int i = 0; i <= N; ++i)
		for (int j = 1; j <= N + 1; ++j)
			for (int k = 0; k <= N; ++k)
				D[i][j][k][0] = D[i][j][k][1] = 1e9;
	X[N + 1] = L;
	D[0][N + 1][0][0] = D[0][N + 1][0][1] = 0;
	for (int i = 0; i <= N; ++i) {
		for (int j = N + 1; j > i; --j) {
			for (int k = 0; k <= N; ++k) {
				if (D[i][j][k][0] != 1e9 || D[i][j][k][1] != 1e9) ans = max(ans, k);

				if (D[i][j][k][0] + X[i + 1] - X[i] <= T[i + 1]) D[i + 1][j][k + 1][0] = min(D[i + 1][j][k + 1][0], D[i][j][k][0] + X[i + 1] - X[i]);
				else D[i + 1][j][k][0] = min(D[i + 1][j][k][0], D[i][j][k][0] + X[i + 1] - X[i]);

				if (D[i][j][k][0] + X[i] + L - X[j - 1] <= T[j - 1]) D[i][j - 1][k + 1][1] = min(D[i][j - 1][k + 1][1], D[i][j][k][0] + X[i] + L - X[j - 1]);
				else D[i][j - 1][k][1] = min(D[i][j - 1][k][1], D[i][j][k][0] + X[i] + L - X[j - 1]);

				if (D[i][j][k][1] + X[j] - X[j - 1] <= T[j - 1]) D[i][j - 1][k + 1][1] = min(D[i][j - 1][k + 1][1], D[i][j][k][1] + X[j] - X[j - 1]);
				else D[i][j - 1][k][1] = min(D[i][j - 1][k][1], D[i][j][k][1] + X[j] - X[j - 1]);

				if (D[i][j][k][1] + L - X[j] + X[i + 1] <= T[i + 1]) D[i + 1][j][k + 1][0] = min(D[i + 1][j][k + 1][0], D[i][j][k][1] + L - X[j] + X[i + 1]);
				else D[i + 1][j][k][0] = min(D[i + 1][j][k][0], D[i][j][k][1] + L - X[j] + X[i + 1]);
			}
		}
	}
	cout << ans;
	return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 75 / 75