#include <bits/stdc++.h>
using namespace std;
const double pi = acos(-1.0);
const int imax = 2147483647;
const int imin = -2147483647;
const long long lmax = 9223372036854775807;
const long long lmin = -9223372036854775807;
long long power(long long a, long long b, long long m) {
  long long p = 1;
  while (b) {
    if (b & 1) p = (p * a) % m;
    b >>= 1;
    a = (a * a) % m;
  }
  return (p % m);
}
int main() {
  int n;
  cin >> n;
  int arr[100005];
  int distinct[100005] = {0}, mp[100005] = {0};
  for (int i = 0; i < n; i++) cin >> arr[i];
  for (int i = n - 1; i >= 0; i--) {
    if (i == n - 1) {
      mp[arr[i]] = 1;
      distinct[i] = 1;
    } else {
      if (mp[arr[i]] == 0) {
        mp[arr[i]] = 1;
        distinct[i] = 1 + distinct[i + 1];
      } else
        distinct[i] = distinct[i + 1];
    }
  }
  memset(mp, 0, sizeof(mp));
  long long ans = 0;
  for (int i = 0; i < n - 1; i++) {
    if (mp[arr[i]] == 0) {
      mp[arr[i]] = 1;
      ans += (long long)distinct[i + 1];
    }
  }
  cout << ans;
  return 0;
}
