def count_Unset_Bits(n) :
      
    cnt = 0;  
    for i in range(1,n + 1) : 
        temp = i;  
        while (temp) :  
            if (temp % 2 == 0) : 
                cnt += 1;  
            temp = temp // 2;  
    return cnt;  
def count_ways(n):
	 
	A = [0] * (n + 1) 
	B = [0] * (n + 1) 
	A[0] = 1
	A[1] = 0
	B[0] = 0
	B[1] = 1
	for i in range(2, n+1): 
		A[i] = A[i - 2] + 2 * B[i - 1] 
		B[i] = A[i - 1] + B[i - 2] 
	return A[n] 