#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define sp ' '
#define en '\n'
#define smin(a, b) a = min(a, b)
#define smax(a, b) a = max(a, b)
using namespace std;
const int N = 1e6 + 2;
const int inf = 2e9;
vector<int> pos[N];
int ans[N];
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int n; cin >> n;
for (int i = 1; i <= n; i++) {
int x; cin >> x;
if (!pos[x + 1].empty()) {
int j = pos[x + 1].back();
pos[x + 1].pop_back();
ans[j] = 0;
}
ans[i] = 1;
pos[x].push_back(i);
}
int sum = 0;
for (int i = 1; i <= n; i++) sum += ans[i];
cout << sum << en;
return 0;
}
