Submission #313376

#	Time	Username	Problem	Language	Result	Execution time	Memory
313376		sofapuden	Collecting Stamps 3 (JOI20_ho_t3)	C++14	100 / 100	121 ms	133368 KiB

ho_t3

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

const int maxn = 204;

ll n,l, X[maxn], T[maxn], dp[maxn][maxn][2][maxn];

int main(){
	ios::sync_with_stdio(0), cin.tie(0);
	memset(dp, 0x3f, sizeof dp);	
	cin >> n >> l;
	for(int i = 1; i <= n; ++i)cin >> X[i];
	X[n+1] = l;
	for(int i = 1; i <= n; ++i)cin >> T[i];
	++n;
	T[0] = -1;
	dp[0][n][0][0] = 0;
	dp[0][n][1][0] = 0;
	
	int ans = 0;
	
	for(int x = n-1; x >= 1; --x){
		for(int i = 0; i+x <= n; ++i){
			int j = i+x;
			for(int k = 0; k <= n; ++k){
				if(i){
					dp[i][j][0][k] = min(dp[i][j][0][k], dp[i-1][j][0][k] + X[i] - X[i-1]);
				}
				if(j != n){
					dp[i][j][1][k] = min(dp[i][j][1][k], dp[i][j+1][1][k] + X[j+1] - X[j]);
				}
				if(k){
					if(i && dp[i-1][j][0][k-1] + X[i] - X[i-1] <= T[i]){
						dp[i][j][0][k] = min(dp[i][j][0][k], dp[i-1][j][0][k-1] + X[i] - X[i-1]);
					}
					if(j != n && dp[i][j+1][1][k-1] + X[j+1] - X[j] <= T[j]){
						dp[i][j][1][k] = min(dp[i][j][1][k], dp[i][j+1][1][k-1] + X[j+1] - X[j]);
					}
				}
				dp[i][j][0][k] = min(dp[i][j][0][k], dp[i][j][1][k] + l - X[j] + X[i]);
				dp[i][j][1][k] = min(dp[i][j][1][k], dp[i][j][0][k] + l - X[j] + X[i]);
				if(min(dp[i][j][0][k],dp[i][j][1][k]) < 10000000000ll)ans = max(ans,k);
			}
		}
	}
					
	
	cout << ans << "\n";
			
			
}

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