def subsetOfNum(arr, n, sum = 0):
	res = [0]
	for i in range(0, n):
		for j in range(i+1, n):
			new_ele = res[i-1]+res[i]
			res.append(new_ele)
	print(res)





if __name__ == "__main__":
	arr = list(map(int, input().split()))
	n = len(arr)
	print(n)
	print(arr)
	subsetOfNum(arr, n)