Submission #367321

#	Time	Username	Problem	Language	Result	Execution time	Memory
367321		piddddgy	Bitaro the Brave (JOI19_ho_t1)	C++11	100 / 100	353 ms	229740 KiB

joi2019_ho_t1

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#define cerr if(false) cerr
#define watch(x) cerr << (#x) << " is " << (x) << endl;
#define endl '\n'
#define ld long double
#define int long long
#define pii pair<int, int>
#define fi first
#define se second
#define sz(a) (int)(a).size()
#define all(x) (x).begin(), (x).end()

const int maxn = 3005;
int n, m;

char a[maxn][maxn];

int psa[5][maxn][maxn];

int query(int c, int i, int j, int ii, int jj) {
    cerr << c << " " << i << " " << j << " " << ii << " " << jj << endl;
    return psa[c][ii][jj] - psa[c][ii][j-1] - psa[c][i-1][jj] + psa[c][i-1][j-1];
}

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

    cin >> n >> m;

    for(int i = 1; i <= n; i++) {
        string s;
        cin >> s;

        for(int j = 1; j <= m; j++) {
            a[i][j] = s[j-1];
            if(a[i][j] == 'J') psa[1][i][j]++;
            else if(a[i][j] == 'O') psa[2][i][j]++;
            else if(a[i][j] == 'I') psa[3][i][j]++;
        }
    }

    for(int c = 1; c <= 3; c++) {
        for(int i = 1; i <= n; i++) {
            for(int j = 1; j <= m; j++) {
                psa[c][i][j] += psa[c][i-1][j] + psa[c][i][j-1] - psa[c][i-1][j-1];
            }
        }
    }

    int ans = 0;
    for(int i = 1; i <= n; i++) {
        for(int j = 1; j <= m; j++) {
            if(a[i][j] == 'J') {
                cerr << "passing in " << i << " " << j << " " << n << " " << j << endl;
                int ocnt = query(2, i, j, i, m);
                int icnt = query(3, i, j, n, j);

                ans += ocnt*icnt;
            }
        }
    }

    cout << ans << endl;
}

/*



Did you read the bounds?
Did you make typos?
Are there edge cases (N=1?)
Are array sizes proper?
Integer overflow?
DS reset properly between test cases?
Is using long longs causing TLE?
Are you using floating points?
*/

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