#include <bits/stdc++.h>
using namespace std;

int main(){
    int n;
    cin >> n;
    vector<int> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }

    vector<bool> zun1(n, false); zun1[0] = true;
    vector<bool> zun2(n, false);

    for (int i = 1; i < n; i++) {
        if (zun1[i-1] == false) {
            zun1[i] = true;
        }
        if (zun2[i-1] == false) {
            zun2[i] = true;
        }
        if (a[i-1] == a[i]) {
            zun1[i] = true;
            zun2[i] = true;
        }
    }

    int cnt = 0, cntt = 0;
    for (int i = 0; i < n; i++) {
        if (zun1[i]) cnt++;
        if (zun2[i]) cntt++;
    }
    cout << max(cnt, cntt) << endl;
    return 0;
}