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Python - Find if there are duplicate values in a list

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):
list1 = []
for n in nums:
if n in list1:
return True
else:
list1.append(n)
return False

obj = Solution()
print(obj.containsDuplicate([1,2,3,4]))
print(obj.containsDuplicate([1,2,3,1]))
OUTPUT
False
True

Second Solution

class Solution:
def containsDuplicate(self, nums):
nums.sort()
for i in range(0, len(nums)-1):
if nums[i]==nums[i+1]:
return True
return False

obj = Solution()
print(obj.containsDuplicate([1,2,3,4]))
print(obj.containsDuplicate([1,2,3,1]))
OUTPUT
False
True

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