Submission #874569

#	Time	Username	Problem	Language	Result	Execution time	Memory
874569		atom	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	177 ms	88896 KiB

joi2019_ho_t1

#include "bits/stdc++.h"
// @JASPER'S BOILERPLATE
using namespace std;
using ll = long long;
#define FOR(i, a, b) for(int i = a; i <= b; i++)
#define FORD(i, a, b) for(int i = a; i >= b; i--)
#define REP(i, b) for(int i = 0; i < b; i++)
#define PER(i, b) for(int i = b - 1; i >= 0; i--)
#define fi first
#define se second
#ifdef JASPER
#include "debug.h"
#else
#define debug(...) 166
#endif

using pii = pair < int, int >;
const int INF = 1e9;
const int MOD = 1e9 + 7;
const int N = 3e3 + 5;

int n, m;
char a[N][N];
int dpO[N][N], dpI[N][N];

void run_case() {
    cin >> n >> m;
    for (int i = 1; i <= n; ++i)
        for (int j = 1; j <= m; ++j)
            cin >> a[i][j];

    for (int j = m; j >= 1; --j) {
        for (int i = 1; i <= n; ++i) {
            dpO[i][j] = (a[i][j] == 'O');
            dpO[i][j] += dpO[i][j + 1];
        }
    }

    for (int i = n; i >= 1; --i) {
        for (int j = 1; j <= m; ++j) {
            dpI[i][j] = (a[i][j] == 'I');
            dpI[i][j] += dpI[i + 1][j];
        }
    }


    ll ans = 0;
    for (int i = 1; i <= n; ++i)
        for (int j = 1; j <= m; ++j)
            if (a[i][j] == 'J')
                ans += 1ll * dpO[i][j] * dpI[i][j];
    cout << ans << "\n";
}

signed main() {
    cin.tie(0) -> sync_with_stdio(0);
    
    int Test = 1;
    //cin >> Test;
    for (int test = 1; test <= Test; test++){

        run_case();
    }
}

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