#include <bits/stdc++.h>
// #include <atcoder/all>
// using namespace atcoder;
#define _overload3(_1,_2,_3,name,...) name
#define _rep(i,n) repi(i,0,n)
#define repi(i,a,b) for(int i=int(a);i<int(b);++i)
#define rep(...) _overload3(__VA_ARGS__,repi,_rep,)(__VA_ARGS__)
#define rrep(i,n) for(int i=int(n-1);i>=int(0);--i)
#define fore(i,a) for(auto &i:a)
#define all(x) x.begin(),x.end() 
#define sz(x) ((int)(x).size())
#define bp(x) (__builtin_popcount((long long)(x)))
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define V vector
#define P pair<int,int>
#define TP tuple<int,int,int>
#define F first
#define S second
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }
using ll = long long;
using ld = long double;
using namespace std;
const int INF = 1001001001;
const ll INFL = 1001001001001001001;
const int MAX = 200005;

int main() {
    int n;cin>>n;
    V<string> x;
    rep(i,n){
        string s,t;cin>>s;
        t=s;
        sort(all(t));
        if(s==t){
            x.pb(s);
        }
    }
    sort(all(x));
    V<V<ll>> dp(2,V<ll>(30));
    int now=0;
    rep(i,sz(x)){
        now=1-now;
        int m=x[i].back()-'a';
        dp[now]=dp[!now];
        rep(j,x[i].front()-'a'+1){
            chmax(dp[now][m],dp[!now][j]+sz(x[i]));
        }
    }

    ll ans=0;
    rep(i,30){
        chmax(ans,dp[now][i]);
    }

    cout<<ans<<endl;
    return 0;

}