minor_than_x.py

class Tree(object):

    def __init__(self, value):
        self.value = value
        self.left = None
        self.right = None

    def add(self, number):
        if number <= self.value:
            if self.left:
                self.left.add(number)
            else:
                self.left = Tree(number)
        else:
            if self.right:
                self.right.add(number)
            else:
                self.right = Tree(number)

    def in_order(self):
        string = ""
        if self.left:
            string += self.left.in_order()
        string += str(self.value)
        if self.right:
            string += self.right.in_order()
        return string

def findNextMinorToX(tree, x):
    if not tree:
        return None

    if x > tree.value:
        return max(findNextMinorToX(tree.right, x), tree.value)
    else:
        return findNextMinorToX(tree.left, x)


t = Tree(7)

t.add(5)
t.add(4)
t.add(3)
t.add(9)
t.add(8)
t.add(10)

x = 6

print "Printing In Order for Tree %s" % t.in_order()
print "Value of X: %s" % str(x)
print "Printing minor value than %s, %s" %(x, str(findNextMinorToX(t, x)))