#include "bits/stdc++.h" using namespace std; using ll = long long; const double pi = acos(-1); #define FOR(i,a,b) for (ll i=(a),__last_##i=(b);i<__last_##i;i++) #define RFOR(i,a,b) for (ll i=(b)-1,__last_##i=(a);i>=__last_##i;i--) #define REP(i,n) FOR(i,0,n) #define RREP(i,n) RFOR(i,0,n) #define __GET_MACRO3(_1, _2, _3, NAME, ...) NAME #define rep(...) __GET_MACRO3(__VA_ARGS__, FOR, REP)(__VA_ARGS__) #define rrep(...) __GET_MACRO3(__VA_ARGS__, RFOR, RREP)(__VA_ARGS__) template ostream& operator<<(ostream& os, const vector& v) { REP(i, v.size()) { if (i)os << " "; os << v[i]; }return os; } template ostream& operator<<(ostream& os, const vector>& v) { REP(i, v.size()) { if (i)os << endl; os << v[i]; }return os; } const ll INF = 1LL << 60; ll MOD = 1000000007; ll _MOD = 1000000009; double EPS = 1e-10; int main() { ll n; ll ans = 0; cin >> n; vector v(n); REP(i, n) { cin >> v[i]; } sort(v.begin(), v.end()); if (n == 1) { cout << 1 << endl; } else { if (v[0] != v[1]) { ans++; } if (v[n - 1] != v[n - 2]) { ans++; } FOR(i, 1, n - 1) { if (v[i] != v[i - 1] && v[i] != v[i + 1]) { ans++; } } cout << ans << endl; } }