Submission #1038631

#	Time	Username	Problem	Language	Result	Execution time	Memory
1038631		khanhtb	Bitaro the Brave (JOI19_ho_t1)	C++14	100 / 100	230 ms	159240 KiB

joi2019_ho_t1

// #pragma GCC optimize("O3,unroll-loops")
// #pragma GCC targt("avx2,bmi,bmi2,popcnt,lzcnt")
#include <bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define ld long double
#define pb push_back
#define pf push_front
#define vi vector<ll>
#define vii vector<vi>
#define pll pair<ll, ll>
#define vpll vector<pll>
#define all(a) a.begin(), a.end()
#define fi first
#define se second
using namespace std;
const ll mod = 998244353; 
const ll inf = 1e18;
const ll blocksz = 320;
const ll N = 3e3+8;
int n,m;
char a[N][N];
ll pre[N][N],suf[N][N];
void solve(){
    cin >> n >> m;
    for(int i = 1; i <= n; i++) {
        for(int j = 1; j <= m; j++){
            cin >> a[i][j];
        }
    }
    for(int i = 1; i <= n; i++){
        for(int j = m; j >= 1; j--){
            if(a[i][j] == 'O') pre[i][j]++;
            pre[i][j] += pre[i][j+1];
        }
    }
    for(int j = 1; j <= m; j++){
        for(int i = n; i >= 1; i--){
            if(a[i][j] == 'I') suf[i][j]++;
            suf[i][j] += suf[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 += pre[i][j]*suf[i][j];
            }
        }
    }
    cout << ans;
}
signed main(){
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);   
    if (fopen("test.inp", "r")){
        freopen("test.inp", "r", stdin);
        freopen("test.out", "w", stdout);
    }
    ll T = 1;
    // cin >> T;
    for (ll i = 1; i <= T; i++){
        solve();
        cout << '\n';
    }
}

Compilation message (stderr)

joi2019_ho_t1.cpp: In function 'int main()':
joi2019_ho_t1.cpp:56:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   56 |         freopen("test.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
joi2019_ho_t1.cpp:57:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   57 |         freopen("test.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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