Submission #224049

#	Time	Username	Problem	Language	Result	Execution time	Memory
224049		shenxy	Collecting Stamps 3 (JOI20_ho_t3)	C++11	100 / 100	165 ms	128760 KiB

ho_t3

#include <cstdio>
#include <algorithm>
#define int long long
using namespace std;
const int INF = 1000000000000000000;
int N, L, X[202], T[202];
int dist[202][202][201][2];
int32_t main() {
	scanf("%lld %lld", &N, &L);
	for (int i = 1; i <= N; ++i) scanf("%lld", &X[i]);
	for (int i = 1; i <= N; ++i) scanf("%lld", &T[i]);
	X[0] = 0;
	X[N + 1] = L;
	for (int i = 0; i < N + 2; ++i) {
		for (int j = 0; j < N + 2; ++j) dist[i][j][0][0] = dist[i][j][0][1] = INF;
	}
	dist[0][N + 1][0][0] = dist[0][N + 1][0][1] = 0;
	for (int i = 0; i <= N; ++i) {
		for (int j = i + 1; j < N + 2; ++j) {
			if (i == 0 && j == N + 1) continue;
			dist[i][j][0][0] = 2 * X[i] + L - X[j];
			dist[i][j][0][1] = 2 * L - 2 * X[j] + X[i];
		}
	}
	int ans = 0;
	for (int i = 1; i <= N; ++i) {
		for (int j = 0; j <= N; ++j) {
			for (int k = N + 1; k > j; --k) {
				dist[j][k][i][0] = dist[j][k][i][1] = INF;
				if (j != 0) dist[j][k][i][1] = min(dist[j][k][i][1], min(dist[j - 1][k][i][1] + X[j] - X[j - 1], dist[j - 1][k][i][0] + L - X[k] + X[j]));
				if (k != N + 1) dist[j][k][i][0] = min(dist[j][k][i][0], min(dist[j][k + 1][i][0] + X[k + 1] - X[k], dist[j][k + 1][i][1] + L - X[k] + X[j]));
				if (j != 0 && min(dist[j - 1][k][i - 1][1] + X[j] - X[j - 1], dist[j - 1][k][i - 1][0] + L - X[k] + X[j]) <= T[j]) dist[j][k][i][1] = min(dist[j][k][i][1], min(dist[j - 1][k][i - 1][1] + X[j] - X[j - 1], dist[j - 1][k][i - 1][0] + L - X[k] + X[j]));
				if (k != N + 1 && min(dist[j][k + 1][i - 1][0] + X[k + 1] - X[k], dist[j][k + 1][i - 1][1] + L - X[k] + X[j]) <= T[k]) dist[j][k][i][0] = min(dist[j][k][i][0], min(dist[j][k + 1][i - 1][0] + X[k + 1] - X[k], dist[j][k + 1][i - 1][1] + L - X[k] + X[j]));
				if (dist[j][k][i][0] < INF || dist[j][k][i][1] < INF) ans = max(ans, i);
			}
		}
	}
	printf("%lld", ans);
	return 0;
}

Compilation message (stderr)

ho_t3.cpp: In function 'int32_t main()':
ho_t3.cpp:9:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld %lld", &N, &L);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~
ho_t3.cpp:10:36: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for (int i = 1; i <= N; ++i) scanf("%lld", &X[i]);
                               ~~~~~^~~~~~~~~~~~~~~
ho_t3.cpp:11:36: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for (int i = 1; i <= N; ++i) scanf("%lld", &T[i]);
                               ~~~~~^~~~~~~~~~~~~~~

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