Submission #909496

#	Time	Username	Problem	Language	Result	Execution time	Memory
909496		a_l_i_r_e_z_a	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	158 ms	89640 KiB

joi2019_ho_t1

// In the name of God

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

typedef long long ll;
typedef long double ld;
typedef pair<ll, ll> pii;
typedef pair<ll, ll> pll;

#define pb push_back
#define S second
#define F first
#define mp make_pair
#define smax(x, y) (x) = max((x), (y))
#define smin(x, y) (x) = min((x), (y))
#define all(x) (x).begin(), (x).end()
#define len(x) ((ll)(x).size())

const int maxn = 3000 + 5;
const int inf = 1e9 + 7;
int n, m, orb[maxn][maxn], ing[maxn][maxn];
string a[maxn];

int32_t main()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    cin >> n >> m;
    for(int i = 0; i < n; i++) cin >> a[i];
    for(int i = 0; i < n; i++){
        for(int j = m - 1; j >= 0; j--) 
            orb[i][j] = orb[i][j + 1] + (a[i][j] == 'O');
    }
    ll ans = 0;
    for(int j = 0; j < m; j++){
        for(int i = n - 1; i >= 0; i--){
            ing[i][j] = ing[i + 1][j] + (a[i][j] == 'I');
            if(a[i][j] == 'J') ans += ing[i][j] * orb[i][j];
        }
    }
    cout << ans << '\n';

    return 0;
}

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