Submission #672432

#	Time	Username	Problem	Language	Result	Execution time	Memory
672432		Alihan_8	Red-blue table (IZhO19_stones)	C++17	100 / 100	86 ms	3296 KiB

stones

#include <bits/stdc++.h>
// include <ext/pb_ds/assoc_container.hpp>
// include <ext/pb_ds/tree_policy.hpp>
// using namespace __gnu_pbds;
using namespace std;
#define all(x) x.begin(), x.end()
#define pb push_back
// define ordered_set tree<int,null_type,less_equal<int>,rb_tree_tag,tree_order_statistics_node_update>
#define mpr make_pair
#define ln '\n'
void IO(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
#define int long long
void solve(){
    int n, m; cin >> n >> m;
    bool rev = false;
    if ( n > m ){
        swap(n, m); rev = true;
    }
    vector <vector<char>> p(n, vector <char> (m, '-'));
    set <pair<int,int>> st;
    for ( int i = 0; i < m; i++ ) st.insert({0, i});
    vector <int> cnt(m, (n+1)/2-1);
    for ( int i = 0; i < n; i++ ){
        int Mx = m/2+1;
        while ( Mx and !st.empty() ){
            auto it = st.begin(); st.erase(st.begin());
            if ( !cnt[it->second] ) continue;
            cnt[it->second]--; Mx--;
            p[i][it->second] = '+';
            st.insert({it->first+1, it->second});
        }
    }
    if ( rev ){
        vector <vector<char>> P(m, vector <char> (n));
        for ( int i = 0; i < n; i++ ){
            for ( int j = m-1; j >= 0; j-- ){
                if ( p[i][j] == '+' ) P[m-1-j][i] = '-';
                else P[m-1-j][i] = '+';
            }
        }
        swap(n, m);
        p = P;
    }
    int score = 0;
    for ( int i = 0; i < n; i++ ){
        int l = 0, r = 0;
        for ( auto j: p[i] ){
            if ( j == '+' ) l++;
            else r++;
        }
        score += l > r;
    }
    for ( int i = 0; i < m; i++ ){
        int l = 0, r = 0;
        for ( int j = 0; j < n; j++ ){
            if ( p[j][i] == '+' ) l++;
            else r++;
        }
        score += r > l;
    }
    cout << score << ln;
    for ( auto i: p ){
        for ( auto j: i ) cout << j;
        cout << ln;
    }
}
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int T; cin >> T;
    while ( T-- ){
        solve();
    }

    cout << '\n';
}

Compilation message (stderr)

stones.cpp: In function 'void IO(std::string)':
stones.cpp:11:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   11 | void IO(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
stones.cpp:11:70: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   11 | void IO(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                                                               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 17 / 17
• Subtask 2: 10 / 10
• Subtask 3: 16 / 16
• Subtask 4: 11 / 11
• Subtask 5: 15 / 15
• Subtask 6: 31 / 31