#include <bits/stdc++.h>
using namespace std;
#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;

int main() {
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit);
    int n;
    cin >> n;
    map<string,int> occ;
    int res = 0;
    for (int i = 0; i < n; i++)
    {
        string s;
        cin >> s;
        if (occ.count(s)) {
            res = max(res, n - (i - occ[s]));
        }
        occ[s] = i;
    }
    cout << res << "\n";
    
}