#include<bits/stdc++.h> using namespace std; struct id{ string be, en; }; int main(){ int n; cin >> n; vector<struct id>dic(n); for(int i = 0; i < n; i++){ string a, b, c, d; cin >> a >> b >> c >> d; dic[i] = {a, d}; } int ans = 0; for(int i = 0; i < n; i++){ string a = dic[i].be, b = dic[i].en; for(int j = 0; j < n; j++){ if(j != i && dic[j].be == a){ string c = dic[j].en; bool flag = true; int l = -1; for(int k = 0; k < n; k++){ if(k != i && k != j && dic[k].be == b && dic[k].en == c){ flag = false; l = k; break; } } if(flag) break; for(int k = 0; k < n; k++) if(k != i && k != j && k != l && dic[k].be == c){ string d = dic[k].en; flag = true; int jj = -1; for(int ii = 0; ii < n; ii++) if(ii != i && ii != j && ii != l && ii != k && dic[ii].be == d && dic[ii].en == a){ jj = ii; flag = false; break; } if(flag) break; flag = true; for(int ii = 0; ii < n; ii++) if(ii != i && ii != j && ii != l && ii != k && ii != jj && dic[ii].be == b && dic[ii].en == d){ flag = false; break; } if(flag) break; ans++; } } } } cout << ans; return 0; }