Submission #867179

#	Time	Username	Problem	Language	Result	Execution time	Memory
867179		dpsaveslives	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	147 ms	115536 KiB

joi2019_ho_t1

#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int MAXN = 3010;
int grid[MAXN][MAXN];
int ing[MAXN][MAXN],orb[MAXN][MAXN];
int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    int H,W; cin >> H >> W; //count for every J how many O's are in the row after it and how many I's are in the column after it
    for(int i = 0;i<H;++i){
        string s; cin >> s;
        for(int j = 0;j<W;++j){
            grid[i][j] = s[j];
        }
    }
    for(int i = 0;i<H;++i){
        int cnt = 0;
        for(int j = W-1;j>=0;--j){
            if(grid[i][j] == 'J'){
                orb[i][j] = cnt;
            }
            else if(grid[i][j] == 'O'){
                cnt++;
            }
        }
    }
    for(int i = 0;i<W;++i){
        int cnt = 0;
        for(int j = H-1;j>=0;--j){
            if(grid[j][i] == 'J'){
                ing[j][i] = cnt;
            }
            else if(grid[j][i] == 'I'){
                cnt++;
            }
        }
    }
    ll ans = 0;
    for(int i = 0;i<H;++i){
        for(int j = 0;j<W;++j){
            if(grid[i][j] == 'J'){
                //cout << ing[i][j] << " " << orb[i][j] << "\n";
                ans += ing[i][j]*orb[i][j];
            }
        }
    }
    cout << ans << "\n";
    return 0;
}

• Subtask 1: 20 / 20
• Subtask 2: 30 / 30
• Subtask 3: 50 / 50