Submission #724848

#	Time	Username	Problem	Language	Result	Execution time	Memory
724848		guagua0407	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	212 ms	17920 KiB

joi2019_ho_t1

//#pragma GCC optimize("O3")
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int,int>
#define f first
#define s second
#define all(x) x.begin(),x.end()
#define _ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

void setIO(string s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}

int main() {_
    int n,m;
    cin>>n>>m;
    char num[n][m];
    for(int i=0;i<n;i++){
        for(int j=0;j<m;j++){
            cin>>num[i][j];
        }
    }
    vector<int> cnt2(m,0);
    for(int j=0;j<m;j++){
        for(int i=0;i<n;i++){
            if(num[i][j]=='I') cnt2[j]++;
        }
    }
    ll ans=0;
    for(int i=0;i<n;i++){
        int cnt=0;
        for(int j=m-1;j>=0;j--){
            if(num[i][j]=='I') cnt2[j]--;
            if(num[i][j]=='O') cnt++;
            if(num[i][j]=='J'){
                ans+=cnt*cnt2[j];
            }
        }
    }
    cout<<ans;
    return 0;
}
//maybe its multiset not set

Compilation message (stderr)

joi2019_ho_t1.cpp: In function 'void setIO(std::string)':
joi2019_ho_t1.cpp:12:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
joi2019_ho_t1.cpp:13:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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