//kanser bitmask sorusu <3
//journey - deco*27
#include <bits/stdc++.h>
using namespace std;
int com[(1<<16)][26], ans[1<<16], gh=0;
int cnt[16][26], n;
string str[16];
int lfms_bt(int x){
int cnt=0;
while(x){
cnt++;
x/=2;
}
return cnt-1; //buraya dikkat!
}
int f(int s){
//cout<<s<<" "<<ans[s]<<" gh\n";
if(ans[s]!=-1) return ans[s]; //s=0 ve 1 stringi kapsar
int add=INT_MAX;
for(int t=(s-1)&s; t!=0; t=(t-1)&s){
//cout<<s<<" "<<t<<" "<<(s^t)<<" :( \n";
add=min(add, f(t)+f(s^t));
}
int ort=0;
for(int i=0; i<26; i++){
ort+=com[s][i];
}
//cout<<add<<" "<<ort<<" ? ";
ans[s]=add-ort;
//cout<<s<<" "<<ans[s]<<" döndürür\n";
return ans[s];
}
signed main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL); cout.tie(NULL);
cin>>n;
memset(cnt, 0, sizeof(cnt));
for(int k=0; k<(1<<n); k++) ans[k]=-1;
ans[0]=0;
for(int i=0; i<n; i++){
cin>>str[i];
for(int j=0; j<str[i].length(); j++){
cnt[i][str[i][j]-'a']++;
}
ans[(1<<i)]=str[i].length();
}
for(int i=0; i<26; i++) com[0][i]=37373737;
for(int k=1; k<(1<<n); k++){ //her set için ortakları bulma
int x=lfms_bt(k);
int dec=k^(1<<x);
for(int i=0; i<26; i++){
com[k][i]=min(cnt[x][i], com[dec][i]);
}
}
cout<<f((1<<n)-1)+1;
return 0;
}
