def ncr_modp(n, r, p):
     
    C = [0 for i in range(r+1)]   
    C[0] = 1
    for i in range(1, n+1): 
        for j in range(min(i, r), 0, -1): 
            C[j] = (C[j] + C[j-1]) % p   
    return C[r] 
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] 