Key cutting

#include <bits/stdc++.h>
#include <iostream>

#define int long long
using namespace std;

void solve()
{
    int n;
    cin >> n;

    vector<int> s;
    s.reserve(n);
    s.push_back(0);

    int cuts = 0;

    for (int i = 0; i < n; i++)
    {
        int a;
        cin >> a;

        while (!s.empty() && a < s.back())
        {
            s.pop_back();
        }
        if (s.empty())
        {
            s.push_back(a);
            cuts++;
            continue;
        }

        if (s.back() == a)
            continue;
        else
        {
            cuts++;
            s.push_back(a);
        }
    }
    cout << cuts;
}

signed main()
{
    int t = 1;
    // cin >> t;
    for (int i = 0; i < t; i++)
        solve();
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED