我在python中使用stdout打印输出,但它保持打印的内容最后有空白,而rsplit()
总是给我一个错误。代码如下。
class Node:
def __init__(self, d):
self.data = d
self.left = None
self.right = None
# function to convert sorted array to a
# balanced BST
# input : sorted array of integers
# output: root node of balanced BST
def sort_array_to_bst(arr):
if not arr:
return None
# find middle
mid = (len(arr)) / 2
mid = int(mid)
# make the middle element the root
root = Node(arr[mid])
# left subtree of root has all
# values <arr[mid]
root.left = sort_array_to_bst(arr[:mid])
# right subtree of root has all
# values >arr[mid]
root.right = sort_array_to_bst(arr[mid + 1:])
return root
# A utility function to print the pre-order
# traversal of the BST
def pre_order(node):
if not node:
return
if root:
sys.stdout.write(node.data + ' ')
pre_order(node.left)
pre_order(node.right)
def no_spaces(s):
return ' '.join(s.rsplit())
if __name__ == '__main__':
arr = []
for line in sys.stdin.readline().strip().split(" "):
arr.append(line)
# arr = [7, 898, 157, 397, 57, 178, 26, 679]
# Output = 178 57 26 157 679 397 898
narr = arr[1:]
print(narr)
narr = sorted(narr, key=int)
root = sort_array_to_bst(narr)
pre_order(root)
我输入7 898 157 397 57 178 26 679
我得到输出178 57 26 157 679 397 898.
.
是为了说明空白,但在实际输出中注意它只是一个空白区域。我试过了
sys.stdout.write(node.data + ' ').rsplit()
但得到:`AttributeError:'int'对象没有属性'rsplit'。我怎么能这样做,还是有其他选择?
以下是仅在元素之间打印空间的一种方法:
if root:
if node != root:
sys.stdout.write(' ')
sys.stdout.write(str(node.data))
pre_order(node.left)
pre_order(node.right)