EvenTree.py

# Program use for how many even tree will be there in given tree.


class node:

    def __init__(self, data):
        self._data = data
        self._children = []

    def getdata(self):
        return self._data

    def getchildren(self):
        return self._children

    def add(self, node):
        self._children.append(node)


class tree:

    def __init__(self):
        self._head = node('header')

    def linktohead(self, node):
        self._head.add(node)

    def countchild(self, node):
        a = 0
        a += len(node.getchildren())
        for child in node.getchildren():
            a += self.countchild(child)
        return a

n, m = map(int, input().split(" "))
a1 = node(1)
for _ in range(m):
    a, b = input().split(" ")
    exec("{0} = node({1})".format("a" + a, a))
    exec("{0}.add({1})".format("a" + b, "a" + a))

tree = tree()
tree.linktohead(a1)
# testcase
dict1 = {}
for z in range(2, n + 1):
    if (eval("tree.countchild(a{})".format(z)) + 1) % 2 == 0:
        dict1["a" + str(z)] = eval("tree.countchild(a{})".format(z)) + 1
print(len(dict1))