Submission #1089635

#	Time	Username	Problem	Language	Result	Execution time	Memory
1089635		dpsaveslives	Collecting Stamps 3 (JOI20_ho_t3)	C++17	100 / 100	111 ms	135508 KiB

ho_t3

#include <bits/stdc++.h>
#define ll long long
using namespace std;
ll dp[205][205][205][2];
int X[205],T[205];
int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    int N,L; 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];
    }

    int ans = 0;
    memset(dp,0x3f,sizeof(dp));
    ll INF = dp[0][0][0][0];
    dp[0][0][0][0] = dp[0][0][0][1] = 0;
    for(int l = 0;l<=N;++l){
        for(int r = 0;r<=N;++r){
            if(l+r >= N) break;
            for(int k = 0;k<=l+r;++k){
                ll tmp = dp[l][r][k][0];
                if(tmp <= INF){
                    dp[l+1][r][k+(tmp+X[N-l+1]-X[N-l] <= T[N-l])][0] = min(dp[l+1][r][k+(tmp+X[N-l+1]-X[N-l] <= T[N-l])][0],tmp+X[N-l+1]-X[N-l]);
                    dp[l][r+1][k+(tmp+L-X[N-l+1]+X[r+1] <= T[r+1])][1] = min(dp[l][r+1][k+(tmp+L-X[N-l+1]+X[r+1] <= T[r+1])][1],tmp+L-X[N-l+1]+X[r+1]);
                }
                tmp = dp[l][r][k][1];
                if(tmp <= INF){
                    dp[l+1][r][k+(tmp+L-X[N-l]+X[r]<=T[N-l])][0] = min(dp[l+1][r][k+(tmp+L-X[N-l]+X[r]<=T[N-l])][0],tmp+L-X[N-l]+X[r]);
					dp[l][r+1][k+(tmp+X[r+1]-X[r]<=T[r+1])][1]=min(dp[l][r+1][k+(tmp+X[r+1]-X[r]<=T[r+1])][1],tmp+X[r+1]-X[r]);
                }
            }
        }
    }
    for(int i = 0;i<=N;++i){
        for(int j = 0;j<=N;++j){
            for(int k = 0;k<=N;++k){
                if(dp[i][j][k][0] != INF){
                    ans = max(ans,k);
                }
                if(dp[i][j][k][1] != INF){
                    ans = max(ans,k);
                }
            }
        }
    }
    cout << ans << "\n";
    return 0;
}

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