Submission #1156138

#	Time	Username	Problem	Language	Result	Execution time	Memory
1156138		trandangquang	Dango Maker (JOI18_dango_maker)	C++20	100 / 100	161 ms	9304 KiB

dango_maker

#include<bits/stdc++.h>
using namespace std;

const int N=3005;

int n,m,dp[N<<1][3],res;
char a[N][N];

bool chk_ver(int x, int y){
    return x-1>=1&&x+1<=n&&a[x-1][y]=='R'&&a[x][y]=='G'&&a[x+1][y]=='W';
}
bool chk_hor(int x, int y){
    return y-1>=1&&y+1<=m&&a[x][y-1]=='R'&&a[x][y]=='G'&&a[x][y+1]=='W';
}

int main(){
    if(fopen("test.inp","r")){
        freopen("test.inp","r",stdin);
        freopen("test.out","w",stdout);
    }
    cin.tie(0)->sync_with_stdio(0);

    cin>>n>>m;
    for(int i=1; i<=n; ++i){
        for(int j=1; j<=m; ++j){
            cin>>a[i][j];
        }
    }

    for(int i=1; i<=m; ++i){
        int x=1,y=i,id=0;
        while(x>=1&&y>=1&&x<=n&&y<=m){
            ++id;
            dp[id][0]=max({dp[id-1][0],dp[id-1][1],dp[id-1][2]});
            dp[id][1]=max(dp[id-1][0],dp[id-1][1])+chk_ver(x,y);
            dp[id][2]=max(dp[id-1][0],dp[id-1][2])+chk_hor(x,y);
            ++x;--y;
        }
        res+=max({dp[id][0],dp[id][1],dp[id][2]});
    }
    for(int i=2; i<=n; ++i){
        int x=i,y=m,id=0;
        while(x>=1&&y>=1&&x<=n&&y<=m){
            ++id;
            dp[id][0]=max({dp[id-1][0],dp[id-1][1],dp[id-1][2]});
            dp[id][1]=max(dp[id-1][0],dp[id-1][1])+chk_ver(x,y);
            dp[id][2]=max(dp[id-1][0],dp[id-1][2])+chk_hor(x,y);
            ++x;--y;
        }
        res+=max({dp[id][0],dp[id][1],dp[id][2]});
    }
    cout<<res<<'\n';
}

Compilation message (stderr)

dango_maker.cpp: In function 'int main()':
dango_maker.cpp:18:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   18 |         freopen("test.inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
dango_maker.cpp:19:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   19 |         freopen("test.out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 13 / 13
• Subtask 2: 20 / 20
• Subtask 3: 67 / 67