Submission #716227

#	Time	Username	Problem	Language	Result	Execution time	Memory
716227		hpesoj	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	324 ms	150252 KiB

joi2019_ho_t1

#include <bits/stdc++.h>
#define int long long
#define pi pair <int, int>
#define ppi pair <pi, int>
#define fi first
#define se second
#define pb push_back
#define all(x) x.begin(), x.end()
#define debug(x) cout << #x << ": " << x << '\n'
#define debug2(x, y) cout << #x << ": " << x << ' ' << #y << ": " << y << '\n'
#define debug3(x, y, z) cout << #x << ": " << x << ' ' << #y << ": " << y << ' ' << #z << ": " << z << '\n'
using namespace std;
mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count());
const int inf = 1000000000;
int h, w, ans;
char grid[3005][3005];
int suffrow[3005][3005], suffcol[3005][3005]; //row count orb, column count ingot
signed main(){
	ios::sync_with_stdio(0), cin.tie(0);
	cin >> h >> w;
	for(int i = 1; i <= h; i++) for(int j = 1; j <= w; j++) cin >> grid[i][j];
	for(int i = 1; i <= h; i++) for(int j = w; j >= 1; j--){
		suffrow[i][j] = suffrow[i][j+1];
		if(grid[i][j] == 'O') suffrow[i][j]++;
	}
	for(int j = 1; j <= w; j++) for(int i = h; i >= 1; i--){
		suffcol[j][i] = suffcol[j][i+1];
		if(grid[i][j] == 'I') suffcol[j][i]++;
	}
	for(int i = 1; i < h; i++) for(int j = 1; j < w; j++){
		if(grid[i][j] != 'J') continue;
		ans += suffrow[i][j+1] * suffcol[j][i+1];
	}
	cout << ans;
}

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