제출 #141039

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
141039		meatrow	Growing Vegetable is Fun 3 (JOI19_ho_t3)	C++17	100 / 100	246 ms	6912 KiB

joi2019_ho_t3

//#pragma GCC optimize("O3")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,tune=native")
//#pragma GCC optimize ("unroll-loops")
#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using ld = long double;

const int N = 405;

int dp[N][N][4][2];
int cnt[3];
int n;
int suf[N][N][3];

void init(int q) {
    for (int i = 0; i < N; i++) {
        for (int j = 0; j < N; j++) {
            for (int t = 0; t < 4; t++) {
                dp[i][j][t][q] = INT32_MAX;
            }
        }
    }
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    cin >> n;
    map<char, int> mp;
    mp['R'] = 0;
    mp['G'] = 1;
    mp['Y'] = 2;
    string s;
    cin >> s;
    vector<int> pos[3];
    for (int i = 0; i < n; i++) {
        cnt[mp[s[i]]]++;
        pos[mp[s[i]]].push_back(i);
    }
    for (int i = 0; i < 3; i++) {
        pos[i].push_back(-1);
        reverse(pos[i].begin(), pos[i].end());
    }
    for (int t = 0; t < 3; t++) {
        for (int j = 0; j < n; j++) {
            for (int i = 1; i <= cnt[t]; i++) {
                suf[i][j][t] = suf[i - 1][j][t] + (pos[t][i] < j);
            }
        }
    }
    init(0);
    dp[cnt[0]][cnt[1]][3][0] = 0;
    for (int i = 0; i < n; i++) {
        int q = i & 1;
        int w = q ^ 1;
        init(w);
        for (int j = 0; j <= cnt[0]; j++) {
            for (int k = 0; k <= min(n - i - j, cnt[1]); k++) {
                for (int t = 0; t < 4; t++) {
                    if (dp[j][k][t][q] == INT32_MAX) {
                        continue;
                    }
                    if (j > 0 && t != 0) {
                        dp[j - 1][k][0][w] = min(dp[j - 1][k][0][w], dp[j][k][t][q] + suf[k][pos[0][j]][1] + suf[n - i - j - k][pos[0][j]][2]);
                    }
                    if (k > 0 && t != 1) {
                        dp[j][k - 1][1][w] = min(dp[j][k - 1][1][w], dp[j][k][t][q] + suf[j][pos[1][k]][0] + suf[n - i - j - k][pos[1][k]][2]);
                    }
                    if (n - i - j - k > 0 && t != 2) {
                        dp[j][k][2][w] = min(dp[j][k][2][w], dp[j][k][t][q] + suf[j][pos[2][n - i - j - k]][0] + suf[k][pos[2][n - i - j - k]][1]);
                    }
                }
            }
        }
    }
    int ans = INT32_MAX;
    for (int i = 0; i < 4; i++) {
        ans = min(ans, dp[0][0][i][n & 1]);
    }
    if (ans == INT32_MAX) {
        cout << -1;
    } else {
        cout << ans;
    }
    return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 55 / 55
• Subtask 3: 15 / 15
• Subtask 4: 25 / 25