# The problem description is very confusing

• "A happy number is a number defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in a cycle which does not include 1."

This description makes people think think that the numbers that "loop endlessly in a cycle which does not include 1" are also happy numbers.

The part "or it loops endlessly in a cycle which does not include 1" should be put in another sentence saying that: unhappy numbers should be like: XXXX.

• ``````class Solution(object):
def isHappy(self, n):
"""
:type n: int
:rtype: bool
"""
def index(n):
if n < 7 and n != 1:
return False
elif n == 1:
return True
else:
sum1 = sum(map(lambda x:int(x)**2,str(n)))
return index(sum1)
return index(n)``````

• I was confused at first and did not pay attention to the endless loop. I agree with you that if it adds some unhappy number examples , that would be better.

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