269

//269
#include <iostream>
#include <cstdio>
using namespace std;

int main(void) {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    int n, a, b, cnt = 0;
    cin >> n;
    for (int i = 0; i < n; ++ i) {
        cin >> a >> b;
        if (a % 2 == 0 && b % 2 == 0 || a % 2 != 0 && b % 2 != 0)
            ++ cnt;
    }
    cout << cnt;
    return 0;
}