Submission #1175080

#	Time	Username	Problem	Language	Result	Execution time	Memory
1175080		trvhung	Bitaro the Brave (JOI19_ho_t1)	C++20	100 / 100	326 ms	79848 KiB

joi2019_ho_t1

#include <bits/stdc++.h>
// #include <ext/rope>
// #include <ext/pb_ds/assoc_container.hpp>

// using namespace __gnu_pbds;
// using namespace __gnu_cxx;
using namespace std;

// #define   ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
#define            ll long long
#define           ull unsigned long long
#define            ld long double
#define            pb push_back
#define  bit(mask, i) ((mask >> i) & 1)
#define            el '\n'
#define             F first
#define             S second

template <class X, class Y> bool maximize(X &x, const Y &y) { return (x < y ? x = y, 1 : 0); }
template <class X, class Y> bool minimize(X &x, const Y &y) { return (x > y ? x = y, 1 : 0); }

const int INF = 1e9;
const ll LINF = 1e18;
const int MOD = 1e9 + 7;
const int MULTI = 0;
const ld eps = 1e-9;
const int dx[4] = {0, 1, 0, -1}, dy[4] = {1, 0, -1, 0}; // R D L U
const int ddx[4] = {-1, 1, 1, -1}, ddy[4] = {1, 1, -1, -1}; // UR DR DL UL
const char cx[4] = {'R', 'D', 'L', 'U'};
const ll base = 31;
const int nMOD = 2;
const ll mods[] = {(ll)1e9 + 10777, (ll)1e9 + 19777, (ll)1e9 + 3, (ll)1e9 + 3777};

const int maxn = 3e3 + 5;
int n, m, row[maxn][maxn], col[maxn][maxn];
char c[maxn][maxn];

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

	for (int i = 1; i <= n; ++i) {
		row[i][m + 1] = 0;
		for (int j = m; j >= 1; --j)
			row[i][j] = row[i][j + 1] + (c[i][j] == 'O');
	}

	for (int j = 1; j <= m; ++j) {
		col[n + 1][j] = 0;
		for (int i = n; i >= 1; --i)
			col[i][j] = col[i + 1][j] + (c[i][j] == 'I');
	}

	ll res = 0;
	for (int i = 1; i <= n; ++i)
		for (int j = 1; j <= m; ++j)
			if (c[i][j] == 'J')
				res += 1LL * row[i][j + 1] * col[i + 1][j];

	cout << res;
}

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

    if (!MULTI) solve();
    else {
        int test; cin >> test;
        while (test--) solve();
    }
    
    return 0;
}

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