Submission #1212125

#	Time	Username	Problem	Language	Result	Execution time	Memory
1212125		biank	Growing Vegetable is Fun 3 (JOI19_ho_t3)	C++20	100 / 100	395 ms	780512 KiB

joi2019_ho_t3

#include <bits/stdc++.h>

using namespace std;

#define forn(i,n) for(int i=0;i<int(n);i++)
#define forsn(i,s,n) for(int i=int(s);i<int(n);i++)
#define dforn(i,n) for(int i=int(n)-1;i>=0;i--)
#define dforsn(i,s,n) for(int i=int(n)-1;i>=int(s);i--)
#define fst first
#define snd second
#define pb push_back
#define eb emplace_back
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()

typedef long long ll;
typedef vector<ll> vll;
typedef vector<int> vi;
typedef pair<int,int> ii;

const int N=405;
const int INF=1e9;

int dp[N][N][N][3];

void chmin(int &x, int v){
    if(x>v) x=v;
}

int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    
    int n;
    string s;
    cin>>n>>s;
    vi pos[3];
    vi pref[3];
    forn(t,3) pref[t].assign(n+1,0);
    forn(i,n){
        forn(t,3) pref[t][i+1]=pref[t][i];
        int t=s[i]=='R'?2:s[i]=='G';
        pos[t].pb(i),pref[t][i+1]++;
    }
    forn(i,N) forn(j,N) forn(k,N) forn(t,3) dp[i][j][k][t]=INF;
    dp[0][0][0][0]=dp[0][0][0][1]=dp[0][0][0][2]=0;
    forn(i,sz(pos[0])+1) forn(j,sz(pos[1])+1) forn(k,sz(pos[2])+1) forn(t,3){
        int idx=t==0?i:t==1?j:k;
        if(idx>=sz(pos[t])) continue;
        int p=pos[t][idx];
        int cost=0;
        forn(t2,3) if(t2!=t){
            int idx2=t2==0?i:t2==1?j:k;
            if(pref[t2][p+1]<idx2) cost+=idx2-pref[t2][p+1];
        }
        int best=INF;
        forn(t2,3) if(t2!=t){
            chmin(best,dp[i][j][k][t2]);
        }
        chmin(dp[i+(t==0)][j+(t==1)][k+(t==2)][t],best+cost);
    }
    int res=INF;
    forn(t,3) chmin(res,dp[sz(pos[0])][sz(pos[1])][sz(pos[2])][t]);
    if(res==INF) cout<<"-1\n";
    else cout<<res<<'\n';
    
    return 0;
}

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