#include <bits/stdc++.h>
using namespace std;
signed main() {
int n; cin >> n;
int a[n][26];
for(int i=0; i<n; i++) {
string s; cin >> s;
for(int j=0; j<26; j++) a[i][j] = 0;
for(char ch : s) a[i][ch-'a']++;
}
vector<int> dp(1<<n, 1e9);
for(int i=0; i<n; i++) {
dp[1<<i] = 0;
for(int j=0; j<26; j++)
dp[1<<i] += a[i][j];
}
for(int s=1; s<(1<<n); s++) {
if(__builtin_popcount(s) == 1) continue;
int len = 0;
for(int j=0; j<26; j++) {
int mn = 1e9;
for(int i=0; i<n; i++)
if(s & (1 << i)) mn = min(mn, a[i][j]);
len += mn;
}
for(int s2=s&(s-1); s2; s2=s&(s2-1))
dp[s] = min(dp[s], dp[s2] + dp[s^s2] - len);
}
cout << dp[(1<<n)-1] + 1 << '\n';
}
