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// #include <bits/stdc++.h>
#define FAST ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);
#include <iostream>
#include <vector>
using namespace std;

#define MIN -1000000
#define MAX 1000000

int main()
{
    FAST int n;
    cin >> n;

    int curr, prevA, prevB;

    cin >> curr;

    int swapA = 0;
    int swapB = 0;

    // A i%0 => >
    // B i%0 => <
    prevA = curr;
    prevB = curr;
    for (int i = 0; i < n - 1; i++)
    {
        // TODO checks for edge cases: -1M +1M => add max to calculation
        cin >> curr;

        if (i % 2)
        {
            // swapA
            if (prevA > curr)
            {
                prevA = curr;
            }
            else
            {
                if (prevA == MIN)
                {
                    swapA += 50000;
                }
                swapA++;
                prevA = MIN;
            }

            // swapB
            if (prevB < curr)
            {
                prevB = curr;
            }
            else
            {
                if (prevB == MAX)
                {
                    swapB += 50000;
                }
                swapB++;
                prevB = MAX;
            }
        }
        else
        {
            // swapA
            if (prevA < curr)
            {
                prevA = curr;
            }
            else
            {
                if (prevA == MAX)
                {
                    swapA += 50000;
                }
                swapA++;
                prevA = MAX;
            }

            // swapB
            if (prevB > curr)
            {
                prevB = curr;
            }
            else
            {
                if (prevB == MIN)
                {
                    swapB += 50000;
                }
                swapB++;
                prevB = MIN;
            }
        }
    }

    cout << min(swapA, swapB) << endl;
}