#include <bits/stdc++.h>
#define all(x) x.begin(), x.end()
#define sz(x) (int) x.size()
#define endl '\n'
#define pb push_back
#define _ ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
using namespace std;
using ll = long long;
using ull = unsigned long long;
using ii = pair<int,int>;
using iii = tuple<int,int,int>;
const int inf = 2e9+1;
const ll mod = 1e9+7;
const ll base = 101;
template<typename X, typename Y> bool ckmin(X& x, const Y& y) { return (y < x) ? (x=y,1):0; }
template<typename X, typename Y> bool ckmax(X& x, const Y& y) { return (x < y) ? (x=y,1):0; }
vector<int>sorted,qnt;
bool cmp(int a,int b){
return qnt[a]>qnt[b];
}
vector<vector<ll>>hsh, revHsh;
vector<string>v;
ll mul[2000001];
void computeHash(int idx){
int n = qnt[idx];
hsh[idx].pb(ll(v[idx][0]-'A'));
for(int i=1;i<n;++i){
ll add = hsh[idx].back()*base+ll(v[idx][i]-'A');
hsh[idx].pb(add);
hsh[idx].back() %= mod;
}
revHsh[idx].pb(ll(v[idx][n-1]-'A'));
for(int i=n-2;i>=0;--i){
ll add = revHsh[idx].back()+mul[n-1-i]*ll(v[idx][i]-'A');
revHsh[idx].pb(add);
revHsh[idx].back() %= mod;
}
}
unordered_map<int,int>dp;
int main(){_
int n;cin>>n;
v.resize(n), sorted.resize(n), qnt.resize(n);
for(int i=0;i<n;++i){
cin>>v[i];
qnt[i] = sz(v[i]);
}
mul[0] = 1ll;
for(int i=1;i<=2e6;++i)mul[i] = (mul[i-1]*base)%mod;
iota(all(sorted),0);
sort(all(sorted), cmp);
hsh.resize(n), revHsh.resize(n);
int best = 0;
for(int i=0;i<n;++i){
int idx = sorted[i];
computeHash(idx);
int m = qnt[idx];
int me = int(hsh[idx][m-1]);
int res = dp[me]+1;
for(int j=0;j<m;++j)if(hsh[idx][j]==revHsh[idx][j])ckmax(dp[int(hsh[idx][j])], res);
ckmax(best, res);
}
cout<<best<<endl;
}
