import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[] a = new int[n];
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        int prev = a[0];
        int ans = 0;
        boolean prevSkip = false;
        for (int num : a) {
            if(prev == num) {
                prevSkip = false;
                ans++;
                //System.out.print("o ");
            } else {
                if (prevSkip) {
                    prevSkip = false;
                    ans++;
                    //System.out.print("o ");
                } else {
                    prevSkip = true;
                    //System.out.print("x ");
                }
            }
            prev = num;
        }
        System.out.println(ans);
    }
}