Submission #864191

#	Time	Username	Problem	Language	Result	Execution time	Memory
864191		MongHwa	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	186 ms	160188 KiB

joi2019_ho_t1

#include <iostream>
using namespace std;

#define ll long long

string stage[3001];
ll psum1[3005][3005], psum2[3005][3005];

int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);

	int h, w;
	cin >> h >> w;

	for(int i = 0; i < h; i++)
		cin >> stage[i];

	for(int i = h-1; i >= 0; i--)
		for(int j = w-1; j >= 0; j--)
		{
			psum1[i][j] = psum1[i][j+1];
			if(stage[i][j] == 'O')
				psum1[i][j]++;

			psum2[j][i] = psum2[j][i+1];
			if(stage[i][j] == 'I')
				psum2[j][i]++;
		}

	ll ans = 0;
	for(int i = 0; i < h; i++)
		for(int j = 0; j < w; j++)
			if(stage[i][j] == 'J')
				ans += psum1[i][j]*psum2[j][i];

	cout << ans << '\n';
}

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