#define _USE_MATH_DEFINES #include <iostream> //cin, cout #include <vector> //vector #include <algorithm> //sort,min,max,count #include <string> //string,getline, to_string #include <cstdlib> //abs(int) #include <utility> //swap, pair #include <deque> //deque #include <climits> //INT_MAX #include <bitset> //bitset #include <cmath> //sqrt, ceil. M_PI, pow, sin #include <ios> //fixed #include <iomanip> //setprecision #include <sstream> //stringstream #include <numeric> //gcd, assumlate #include <random> //randam_device #include <limits> //numeric_limits #include <time.h> //tm using namespace std; constexpr int64_t D_MOD = 1000000007; constexpr int64_t F_MOD = 998244353; int main() { int N; cin >> N; vector<string> S(N); for (int i = 0; i < N; i++) { cin >> S.at(i); } vector<string> A; for (int i = 0; i < N - 1; i++) { for (int j = i + 1; j < N; j++) { A.push_back(S.at(i) + S.at(j)); A.push_back(S.at(j) + S.at(i)); } } sort(A.begin(), A.end()); A.erase(unique(A.begin(), A.end()), A.end()); cout << A.size() << endl; return 0; }