面试

面试题

1. Largest Sum Contiguous Subarray

def maxSubArraySum(a,size):

return max_so_far

2. check if a binary tree is BST or not

# Python program to check if a binary tree is bst or not

# A binary tree node

class Node:

# Constructor to create a new node

def __init__(self, data):

self.data = data

self.left = None

self.right = None

# Returns true if the given tree is a binary search tree

# (efficient version)

def isBST(node):

return (isBSTUtil(node, INT_MIN, INT_MAX))

# Retusn true if the given tree is a BST and its values

# >= min and <= max

def isBSTUtil(node, mini, maxi):

# Driver program to test above function

root = Node(4)

root.left = Node(2)

root.right = Node(5)

root.left.left = Node(1)

root.left.right = Node(3)

if (isBST(root)):

print "Is BST"

else:

print "Not a BST"