This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
const int N = 1e6 + 5;
typedef long long ll;
int n, a[N], ans, lst;
set<pair<int, int>> st;
int main() {
//    freopen("money.in", "r", stdin);
//    freopen("money.out", "w", stdout);
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
    }
    for (int i = 1; i <= n; i++) {
        st.insert({a[i], i});
        if (lst == a[i])
            continue;
        lst = a[i];
        auto id = st.find({a[i], i});
        if (id == st.begin()) {
            ans++;
            continue;
        }
        id--;
        if ((*id).second == i - 1) {
            continue;
        }
        id = st.lower_bound({a[i], -1});
        if (id == st.begin()) {
            ans++;
            continue;
        }
        id--;
        if ((*id).second == i - 1) {
            st.erase({a[i], i});
            continue;
        }
        ans++;
    }
    cout << ans;
}
/**
6
1 5 2 5 5 6
**/
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