// Problem: A. 分组
// Contest: undefined - NOI2024省选训练赛 52
// URL: http://119.28.3.174/contest/970/problem/546
// Memory Limit: 1024 MB
// Time Limit: 1000 ms
// 
// Powered by CP Editor (https://cpeditor.org)

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define eps 1e-8
#define inf 0x3f3f3f3f
#define INF 0x3f3f3f3f3f3f3f3f
int n;
string s[5005];
int tr[1000005][26],vis[1000005];
int tot=0;
int fa[1000005];
int cnt[1000005];
vector<int>v[55];
int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cin>>n;
	for(int i=1;i<=n;i++)cin>>s[i];
	for(int i=1;i<=n;i++)reverse(s[i].begin(),s[i].end());
	for(int i=1;i<=n;i++){
		int cur=0;
		for(int j=0;j<(int)s[i].size();j++){
			int c=s[i][j]-'A';
			if(tr[cur][c]==0){
				tr[cur][c]=++tot;
				fa[tot]=cur;
				v[j+1].push_back(tot);
			}
			cur=tr[cur][c];
			cnt[cur]++;
		}
	}
	int ans=0;
	for(int i=50;i>=1;i--){
		for(int x:v[i])if(cnt[x]>=2){
			// cout<<x<<endl;
			int cur=x;
			while(cur){
				cnt[cur]-=2;
				cur=fa[cur];
			}
			ans+=2;
		}
	}
	cout<<ans;
	return 0;
}
//quod erat demonstrandum