#include <bits/stdc++.h>
#include <vector>
using namespace std;
int inf=100000000;
using ll=long long;
using pint=pair<int,int>;
using pll=pair<ll,ll>;
using pque_int=priority_queue<int>;
#define rep(i,n) for (int i=0; i < (int) n; i++)
#define _GLIBCXX_DEBUG
template<typename T> inline bool chmax(T &a, T b) { return ((a < b) ? (a = b, true) : (false)); }
template<typename T> inline bool chmin(T &a, T b) { return ((a > b) ? (a = b, true) : (false)); }
int VecMax(vector<int> &v) {
    int output=-inf;
    rep(i,v.size()) chmax(output,v[i]);
    return output;
}
int VecMin(vector<ll> &v) {
    ll output=inf;
    rep(i,v.size()) chmin(output,v[i]);
    return output;
}
ll VecSum(vector<int> &v) {
    ll output=0;
    rep(i,v.size()) output+=v[i];
    return output;
}
ll pow(ll a,ll n) {
    ll output=1;
    while (n>0) output*=a;
    return output;
}
int dir(char c) {
    if (c=='L') return 3;
    else if (c=='R') return 1;
    else if (c=='U') return 2;
    else return 0;
}

int main() {
    int N;
    cin >> N;
    vector<string> s;
    rep(i,N) cin >> s[i];

    set<string> t;
    rep(i,N) {
        rep(j,N) {
            string ns=s[i]+s[j];
            t.insert(ns);
        }
    }
    cout << t.size() << endl;
}