Submission #289659

#	Time	Username	Problem	Language	Result	Execution time	Memory
289659		rocks03	Bitaro the Brave (JOI19_ho_t1)	C++14	100 / 100	483 ms	118392 KiB

joi2019_ho_t1

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pld pair<long double, int>
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pb push_back
#define ff first
#define ss second
#define SZ(x) ((int)(x).size())
#define ld long double
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const int MAXN = 3e3+100;
int H, W, a[MAXN][MAXN], cnt[2+1][MAXN][MAXN];

void read(){
    cin >> H >> W;
    for(int i = 0; i < H; i++){
        string s; cin >> s;
        for(int j = 0; j < W; j++){
            if(s[j] == 'J')
                a[i][j] = 0;
            else if(s[j] == 'O')
                a[i][j] = 1;
            else if(s[j] == 'I')
                a[i][j] = 2;
        }
    }
    for(int i = 0; i < H; i++){
        for(int j = W-1; j >= 0; j--){
            cnt[1][i][j] += cnt[1][i][j+1];
            if(a[i][j] == 1)
                cnt[1][i][j]++;
        }
    }
    for(int j = 0; j < W; j++){
        for(int i = H-1; i >= 0; i--){
            cnt[2][i][j] += cnt[2][i+1][j];
            if(a[i][j] == 2)
                cnt[2][i][j]++;
        }
    }
}

void solve(){
    read();
    ll ans = 0;
    for(int i = 0; i < H; i++){
        for(int j = 0; j < W; j++){
            if(a[i][j] == 0){
                ans += cnt[1][i][j] * cnt[2][i][j];
            }
        }
    }
    cout << ans;
}

int main(){
    ios_base::sync_with_stdio(false);
    solve();
    return 0;
}

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