# Problem

Given an array of integers, find if the array contains any duplicates.

Your function should return true if any value appears at least twice in the array, and it should return false if every element is distinct.

Example 1:

``````Input: [1,2,3,1]
Output: true
``````

Example 2:

``````Input: [1,2,3,4]
Output: false
``````

Example 3:

``````Input: [1,1,1,3,3,4,3,2,4,2]
Output: true
``````

# Python3

``````# Given an array of integers, find if the array contains any duplicates.
#
# Your function should return true if any value appears at least twice in the array, and it should return false
# if every element is distinct.
#
# Example 1:
#
# Input: [1,2,3,1]
# Output: true
# Example 2:
#
# Input: [1,2,3,4]
# Output: false
# Example 3:
#
# Input: [1,1,1,3,3,4,3,2,4,2]
# Output: true

class Solution:
def containsDuplicate(self, nums):
"""
:type nums: List[int]
:rtype: bool
"""
temp_dict = {}
for val in nums:
if val in temp_dict:
return True
temp_dict[val] = val
return False

def containsDuplicate_via_set(self, nums):
"""
:type nums: List[int]
:rtype: bool
"""
return len(nums) != len(set(nums))
``````

Thanks a lot.