#include <bits/stdc++.h>
using namespace std;
const int N = 6e1;
map<string, int> mp;
int n;
int answer = 1;
string To(string a) {
  for (int i = 0; i < a.size(); i++)
    if (a[i] > 'Z') a[i] = a[i] - 32;
  return a;
}
int main() {
  mp["POLYCARP"] = 1;
  cin >> n;
  for (int i = 0; i < n; i++) {
    string n1, r, n2;
    cin >> n1 >> r >> n2;
    n1 = To(n1);
    n2 = To(n2);
    mp[n1] = mp[n2] + 1;
    answer = max(answer, mp[n1]);
  }
  cout << answer;
}
