Submission #467570

#	Time	Username	Problem	Language	Result	Execution time	Memory
467570		MN22	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	383 ms	88404 KiB

joi2019_ho_t1

#pragma GCC optimize("O3")
#include <bits/stdc++.h>

#define F first
#define S second
#define pb push_back
#define ll long long
#define pii pair<int,int>
#define pll pair<ll,ll>
#define endl "\n"
#define yn ynnnnnn

using namespace std;

const int INF = 1000000007;
const int N = 3005;

int dpi[N][N], dpo[N][N];
char a[N][N];
int h, w;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin >> h >> w;
    for(int i = 1; i <= h; i++) {
        for(int j = 1; j <= w; j++) {
            cin >> a[i][j];
        }
    }
    for(int j = 1; j <= w; j++) {
        for(int i = 1; i <= h; i++) {
            if(a[i][j] == 'I') {
                dpi[i][j] = dpi[i-1][j] + 1;
            } else {
                dpi[i][j] = dpi[i-1][j];
            }
        }
    }
    for(int i = 1; i <= h; i++) {
        for(int j = 1; j <= w; j++) {
            if(a[i][j] == 'O') {
                dpo[i][j] = dpo[i][j-1] + 1;
            } else {
                dpo[i][j] = dpo[i][j-1];
            }
        }
    }
    int ansi, anso;
    ll res = 0;
    for(int i = 1; i <= h; i++) {
        for(int j = 1; j <= w; j++) {
            if(a[i][j] == 'J') {
                ansi = dpi[h][j] - dpi[i-1][j];
                anso = dpo[i][w] - dpo[i][j-1];
                //cout << ansi << " " << anso << endl;
                res += 1ll * ansi * anso;
            }
        }
    }
    cout << res << endl;
    return 0;
}

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