Submission #647470

#	Time	Username	Problem	Language	Result	Execution time	Memory
647470		Astrayt	Collecting Stamps 3 (JOI20_ho_t3)	C++17	100 / 100	79 ms	66388 KiB

ho_t3

//君の手を握ってしまったら
//孤独を知らないこの街には
//もう二度と帰ってくることはできないのでしょう
//君が手を差し伸べた 光で影が生まれる
//歌って聞かせて この話の続き
//連れて行って見たことない星まで
//さユリ - 花の塔
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define int ll
#define starburst ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define pii pair<int,int>
#define pb push_back
#define ff first
#define ss second

template<typename T> void chmin(T &a, T b){if(a > b) a = b;}
template<typename T> void chmax(T &a, T b){if(a < b) a = b;}

int dp[205][205][205][2];

void solve(){
    int N, L, ans = 0; cin >> N >> L;
    vector<int> X(N + 2, 0), T(N + 2, 0);
    for(int i = 1; i <= N; ++i) cin >> X[i];
    for(int i = 1; i <= N; ++i) cin >> T[i];
    X[N + 1] = L;
    for(int i = 0; i <= N; ++i){
        for(int j = 0; i + j <= N; ++j){
            for(int k = 0; k <= N; ++k){
                dp[i][j][k][0] = dp[i][j][k][1] = (1ll<<60);
            }
        }
    }
    dp[0][0][0][0] = dp[0][0][0][1] = 0;
    for(int i = 0; i <= N; ++i){
        for(int j = 0; i + j <= N; ++j){
            for(int k = 0; k <= i + j; ++k){
                int t1 = X[N - j + 1] - X[N - j], t2 = X[i] + L - X[N - j];
                chmin(dp[i][j + 1][k + (dp[i][j][k][1] + t1 <= T[N - j])][1], dp[i][j][k][1] + t1);
                chmin(dp[i][j + 1][k + (dp[i][j][k][0] + t2 <= T[N - j])][1], dp[i][j][k][0] + t2);
                t1 = X[i + 1] - X[i], t2 = L - X[N - j + 1] + X[i + 1];
                chmin(dp[i + 1][j][k + (dp[i][j][k][0] + t1 <= T[i + 1])][0], dp[i][j][k][0] + t1);
                chmin(dp[i + 1][j][k + (dp[i][j][k][1] + t2 <= T[i + 1])][0], dp[i][j][k][1] + t2);
            }
        }
    }
    for(int i = 0; i <= N; ++i){
        for(int j = 0; i + j <= N; ++j){
            for(int k = 0; k <= i + j; ++k){
                if(dp[i][j][k][0] < (1ll<<60)) chmax(ans, k);
                if(dp[i][j][k][1] < (1ll<<60)) chmax(ans, k);
            }
        }
    }
    cout << ans << '\n';
}

signed main(){
    starburst
    int t = 1; //cin >> t;
    while(t--) solve();
}

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