#include<iostream>
#include<fstream>
using namespace std;

int main()
{
	ifstream infile("del.inp");
	ofstream outfile("del.out");

	long long a[99999],n,tong = 0;
	int dem=0,i,j;
	
	infile>>n;
	for(i=0;i<n;i++)
	{
		infile>>a[i];
		tong+=a[i];
	}
	
	for(i=0;i<n-1;i++)
	{
		tong = tong - a[i];
		for(j = i+1;j<n;j++)
		{
			tong = tong -a[j];
			if(tong%2==0)
				dem++;
			tong = tong + a[i];		
		}
		tong=tong+a[i];
	}
		
	outfile<<dem;
	
	infile.close();
	outfile.close();
return 0;
}