COW Gymnastics

    1#include <bits/stdc++.h>
    2 
    3using namespace std;
    4 
    5int main(){
    6    ios::sync_with_stdio(0);
    7    cin.tie(0);
    8    int n, k;
    9    cin >> n >> k;
    10    vector<vector<pair<int, int>>> all(n - 1);
    11    vector<pair<int, int>> first;
    12    for(int i = 0; i < n; i++){
    13        vector<int> v(k);
    14        for(int j = 0; j < k; j++){
    15            cin >> v[j];;
    16        }
    17        for(int j = 0; j < v.size() - 1; j++){
    18            for(int m = j + 1; m < v.size(); m++){
    19                int larger = v[j], smaller = v[m];
    20                if(i == 0){
    21                    first.emplace_back(larger, smaller);
    22                } else {
    23                    all[i - 1].push_back({larger, smaller});
    24                }
    25            }
    26        }
    27    }
    28    int ans = first.size();
    29    for(auto p1 : first){
    30        for(int i = 0; i < all.size(); i++){
    31            if(find(all[i].begin(), all[i].end(), p1) == all[i].end()){
    32                ans--; break;
    33            }
    34        }
    35    }
    36    cout << ans << '\n';
    37    return 0;
    38}