Submission #720665

#	Time	Username	Problem	Language	Result	Execution time	Memory
720665		Juan	Collecting Stamps 3 (JOI20_ho_t3)	C++17	5 / 100	22 ms	7416 KiB

ho_t3

#include<bits/stdc++.h>
using namespace std;
#define int long long
const int maxn = 2e2 + 5;

int ans = 0, L;
bool mark[maxn][maxn][maxn][2];
int T[maxn], X[maxn];

void solve(int l, int r, int s, int d, int t){
	if(mark[l][r][s][d]) return;
	mark[l][r][s][d] = true;
	ans = max(ans, s);
	if(l==r-1) return;

	if(d==0){
		int t1 = X[l+1]-X[l];
		int add1 = (t1+t <= T[l+1]);

		int t2 = X[l]+(L-X[r-1]);
		int add2 = (t2+t <= T[r-1]);

		solve(l+1, r, s+add1, d, t+t1);
		solve(l, r-1, s+add2, 1-d, t+t2);
	}
	else{
		int t1 = X[r]-X[r-1];
		int add1 = (t1+t <= T[r-1]);

		int t2 = X[l+1]+(L-X[r]);
		int add2 = (t2+t <= T[l+1]);

		solve(l, r-1, s+add1, d, t+t1);
		solve(l+1, r, s+add2, 1-d, t+t2);
	}
}

int32_t main(){
	int n; cin >> n >> L;
	for(int i = 1; i <= n; i++) cin >> X[i];
	for(int i = 1; i <= n; i++) cin >> T[i];

	solve(0, n+1, 0, 0, 0);

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

• Subtask 1: 5 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 75