#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
  #include "settings/debug.cpp"
  #define _GLIBCXX_DEBUG
#else
  #define Debug(...) void(0)
#endif
using ll = long long;
#define rep(i, n) for (int i = 0; i < (n); ++i)

int main() {
  int n;
  cin >> n;
  map<string, int> mp;
  rep(i, n) {
    string s;
    cin >> s;
    mp[s]++;
  }
  pair<string, int> maxim = { "", 0 };
  for (auto p : mp) {
    if (p.second >= maxim.second) {
      maxim = p;
    }
  }
  cout << maxim.first.size() - 2 << endl;
  return 0;
}