Submission #866030

#	Time	Username	Problem	Language	Result	Execution time	Memory
866030		guagua0407	Growing Vegetable is Fun 3 (JOI19_ho_t3)	C++17	100 / 100	196 ms	8276 KiB

joi2019_ho_t3

//#pragma GCC optimize("O3")
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int,int>
#define f first
#define s second
#define all(x) x.begin(),x.end()
#define _ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

void setIO(string s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}

const int mxn=405;
ll dp[mxn][mxn][3];
ll tmp[mxn][mxn][3];
int cnt[mxn][3];
ll inf=1e18;
map<char,int> mp;

ll bs(ll a){
    return max(0ll,a);
}

int main() {_
    int n;
    cin>>n;
    string str;
    cin>>str;
    str="."+str;
    vector<int> vec(n+1);
    mp['R']=0;
    mp['G']=1;
    mp['Y']=2;
    for(int i=1;i<=n;i++){
        vec[i]=mp[str[i]];
    }
    for(int i=1;i<=n;i++){
        cnt[i][0]=cnt[i-1][0];
        cnt[i][1]=cnt[i-1][1];
        cnt[i][2]=cnt[i-1][2];
        cnt[i][vec[i]]++;
    }
    vector<int> pos[3];
    pos[0].push_back(0);
    pos[1].push_back(0);
    pos[2].push_back(0);
    for(int i=1;i<=n;i++){
        pos[vec[i]].push_back(i);
    }
    //return 0;
    for(int j=0;j<=n;j++){
        for(int k=0;k<=n;k++){
            for(int t=0;t<3;t++){
                dp[j][k][t]=1e18;
            }
        }
    }
    dp[0][0][0]=dp[0][0][1]=dp[0][0][2]=0;
    for(int i=1;i<=n;i++){
        for(int j=0;j<=n;j++){
            for(int k=0;k<=n;k++){
                for(int t=0;t<3;t++){
                    tmp[j][k][t]=1e18;
                }
            }
        }
        for(int j=0;j<=min(cnt[n][0],i);j++){
            for(int k=0;k<=min(cnt[n][1],i-j);k++){
                int r=i-j-k;
                if(r<0 or cnt[n][2]<r) continue;
                if(j>0){
                    int ps=pos[0][j];
                    tmp[j][k][0]=min(dp[j-1][k][1] , dp[j-1][k][2])+bs(cnt[ps][1]-k)+bs(cnt[ps][2]-r);
                }
                if(k>0){
                    int ps=pos[1][k];
                    tmp[j][k][1]=min(dp[j][k-1][0] , dp[j][k-1][2])+bs(cnt[ps][0]-j)+bs(cnt[ps][2]-r);
                }
                if(r>0){
                    int ps=pos[2][r];
                    tmp[j][k][2]=min(dp[j][k][0] , dp[j][k][1])+bs(cnt[ps][0]-j)+bs(cnt[ps][1]-k);
                }
                /*for(int tp=0;tp<3;tp++){
                    cout<<i<<' '<<j<<' '<<k<<' '<<tp<<' '<<dp[i][j][k][tp]<<'\n';
                }*/
            }
        }
        for(int j=0;j<=n;j++){
            for(int k=0;k<=n;k++){
                for(int t=0;t<3;t++){
                    dp[j][k][t]=min(tmp[j][k][t],inf);
                }
            }
        }
    }
    ll ans=*min_element(dp[cnt[n][0]][cnt[n][1]],dp[cnt[n][0]][cnt[n][1]]+3);
    cout<<(ans>=1e18?-1:ans)<<'\n';
    return 0;
}
//maybe its multiset not set
//dp[i][j][k][type] 前 i 個有 j 個 R, k 個 G, 最後一個東西是 type
/*
dp[i][j][k][type]=dp[i-1][

YYGYYYGGGGRGYYGRGRYG
*/

Compilation message (stderr)

joi2019_ho_t3.cpp: In function 'void setIO(std::string)':
joi2019_ho_t3.cpp:12:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
joi2019_ho_t3.cpp:13:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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