def nCr_mod_p(n, r, p):
	 
	if (r > n- r): 
		r = n - r 
	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] 