#include<bits/stdc++.h>
#define ll long long

using namespace std;

const int N = 1e5 + 10;
int ch[N][26], ne[N], tot, n, dep[N];
bool st[N], vis[N];
void insert(string &s)
{
    int p = 0;
    for (auto k : s)
    {
        if (!ch[p][k - 'a'])ch[p][k - 'a'] = ++tot, dep[tot] = dep[p] + 1;
        p = ch[p][k - 'a'];
    }
    st[p] = 1;
}

void solve()
{
    cin >> n;
    while (n--)
    {
        string s; cin >> s;
        insert(s);
    }
    queue<int>q;
    for (int i = 0; i < 26; i++)
    {
        int j = ch[0][i];
        if (st[j])q.push(j), vis[j] = 1;
    }
    int res = 0;
    while (!q.empty())
    {
        int u = q.front(); q.pop();
        res = max(res, dep[u]);
        for (int i = 0; i < 26; i++)
        {
            int v = ch[u][i];
            if (v)
            {
                ne[v] = ch[ne[u]][i];
                if (st[v] && vis[ne[v]])q.push(v), vis[v] = 1;
            }
        }
    }
    cout << res;
}

int main()
{
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    int t = 1;
    while (t--)solve();
    return 0;
}