Submission #1310390

#	Time	Username	Problem	Language	Result	Execution time	Memory
1310390		syanvu	Growing Vegetable is Fun 3 (JOI19_ho_t3)	C++20	100 / 100	61 ms	57096 KiB

joi2019_ho_t3

// #pragma optimize ("g",on)
// #pragma GCC optimize ("inline")
// #pragma GCC optimize ("Ofast")
// #pragma GCC optimize ("unroll-loops")
// #pragma GCC optimize ("03")
#include <bits/stdc++.h>

#define pb push_back
#define SS ios_base::sync_with_stdio(0);cin.tie(nullptr);cout.tie(nullptr);
#define int long long
#define all(v) v.begin(),v.end()
using namespace std;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());

const int N = 4e5 + 1, inf = 1e9 + 1, mod = 998244353;

void solve(){
    int n;
    cin >> n;
    string s;
    cin >> s;
    s = '!' + s;
    int a[n + 1] = {};
    int cnt[3] = {}, pos[n + 1][3] = {}, pref[n + 1][3] = {};
    for(int i = 1; i <= n; i++){
        if(s[i] == 'R') a[i] = 0;
        if(s[i] == 'G') a[i] = 1;
        if(s[i] == 'Y') a[i] = 2;
        cnt[a[i]]++;
        pos[cnt[a[i]]][a[i]] = i;
        for(int j = 0; j < 3; j++) pref[i][j] = cnt[j];
    }
    int dp[cnt[0] + 1][cnt[1] + 1][cnt[2] + 1][3] = {};
    for(int i = 0; i <= cnt[0]; i++){
        for(int j = 0; j <= cnt[1]; j++){
            for(int k = 0; k <= cnt[2]; k++){
                for(int d = 0; d < 3; d++) dp[i][j][k][d] = inf;
            }
        }
    }
    dp[0][0][0][0] = dp[0][0][0][1] = dp[0][0][0][2] = 0;
    for(int a = 0; a <= cnt[0]; a++){
        for(int b = 0; b <= cnt[1]; b++){
            for(int c = 0; c <= cnt[2]; c++){
                for(int l = 0; l < 3; l++){
                    if(dp[a][b][c][l] == inf) continue;
                    if(l != 0 && a + 1 <= cnt[0]){
                        int p = pos[a + 1][0];
                        dp[a + 1][b][c][0] = min(dp[a + 1][b][c][0], dp[a][b][c][l] + max(0ll, pref[p][1] - b) + max(0ll, pref[p][2] - c));
                    }
                    if(l != 1 && b + 1 <= cnt[1]){
                        int p = pos[b + 1][1];
                        dp[a][b + 1][c][1] = min(dp[a][b + 1][c][1], dp[a][b][c][l] + max(0ll, pref[p][0] - a) + max(0ll, pref[p][2] - c));
                    }
                    if(l != 2 && c + 1 <= cnt[2]){
                        int p = pos[c + 1][2];
                        dp[a][b][c + 1][2] = min(dp[a][b][c + 1][2], dp[a][b][c][l] + max(0ll, pref[p][1] - b) + max(0ll, pref[p][0] - a));
                    }   
                }
            }
        }
    }
    int ans = inf;
    for(int l = 0; l < 3; l++) ans = min(ans, dp[cnt[0]][cnt[1]][cnt[2]][l]);
    cout << (ans >= inf ? -1 : ans);
}

signed main(){
    SS
    // freopen("trains.in", "r", stdin);
    // freopen("trains.out", "w", stdout);

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

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