#include <stdio.h>


int main() {
    int n;
    scanf("%d", &n);
    int prethoden = 0;
    int brojac = 0;
    for(int i = 0; i < n; i++) {
        int x;
        scanf("%d", &x);

        if(prethoden != 0) {
            if(prethoden % 2 == 0 && x % 2 == 0) {
                brojac++;
            }
            else if(prethoden % 2 == 1 && x % 2 == 1) {
                brojac++;
            }
        }
        prethoden = x;

    }
    printf("%d\n", brojac);
    return 0;
}