Submission #503341

#	Time	Username	Problem	Language	Result	Execution time	Memory
503341		qwerasdfzxcl	Vim (BOI13_vim)	C++14	60 / 100	735 ms	61568 KiB

vim

#include <bits/stdc++.h>

typedef long long ll;
using namespace std;
int dp[5050][5050], nxt[10][5050], prv[5050];
vector<int> E, pos;

int main(){
    cin.tie(NULL);
    ios_base::sync_with_stdio(false);
    int n;
    string a;
    cin >> n >> a;
    if (n>5000) {printf("0\n"); return 0;}
    string::iterator s = a.begin()-1;

    int pt[10] = {0};
    E.push_back(0);
    for (int i=1;i<=n;i++){
        if (s[i]=='e'){
            E.push_back(i);
            prv[i] = (int)E.size()-1;
        }
        else{
            while(pos.size()<E.size()) pos.push_back(i);
            prv[i] = prv[i-1];
            for (int j=pt[s[i]-'a'];j<i;j++) nxt[s[i]-'a'][j] = i;
            pt[s[i]-'a'] = i;
        }
    }
    for (int j=0;j<10;j++){
        for (int i=pt[j];i<=n;i++) nxt[j][i] = 1e9;

        //for (int i=1;i<=n;i++) printf("%d ", nxt[j][i]);
        //printf("\n");
    }

    /*for (auto &x:E) printf("%d ", x);
    printf("\n");
    for (auto &x:pos) printf("%d ", x);
    printf("\n");
    for (int i=1;i<=n;i++) printf("%d ", prv[i]);
    printf("\n");*/

    if (E.empty()){
        printf("0\n"); return 0;
    }

    for (int i=0;i<(int)E.size();i++){
        fill(dp[i], dp[i]+n+1, 1e9);
    }
    dp[0][1] = 0;

    for (int i=0;i<(int)E.size();i++){
        for (int j=1;j<=n;j++){
            for (int k=0;k<10;k++){
                int idx = nxt[k][j];
                if (idx==1e9) continue;
                if (prv[idx]>i) dp[prv[idx]][pos[i+1]] = min(dp[prv[idx]][pos[i+1]], dp[i][j] + (idx - E[i+1]) + (prv[idx] - i) + 2);
                dp[i][idx] = min(dp[i][idx], dp[i][j] + 2);
            }
        }
    }

    //printf("%d\n", nxt[3][pos[0]]);
    //printf("%d\n", dp[0][0] + (6 - E[0]));

    int ans = 1e9;
    for (int j=1;j<=n;j++) ans = min(ans, dp[(int)E.size()-1][j]);
    printf("%d\n", ans);
    return 0;
}

• Subtask 1: 50 / 50
• Subtask 2: 10 / 10
• Subtask 3: 0 / 40