Python: Find whether a given array of integers contains any duplicate element

Last update on March 28 2025 12:51:50 (UTC/GMT +8 hours)

14. Check if an Array Contains Any Duplicate Elements

Write a Python program to find out if a given array of integers contains any duplicate elements. Return true if any value appears at least twice in the array, and return false if every element is distinct.

Sample Solution:

Python Code :

def test_duplicate(array_nums):
    nums_set = set(array_nums)    
    return len(array_nums) != len(nums_set)     
print(test_duplicate([1,2,3,4,5]))
print(test_duplicate([1,2,3,4, 4]))
print(test_duplicate([1,1,2,2,3,3,4,4,5]))

Sample Output:

False
True
True

For more Practice: Solve these Related Problems:

• Write a Python program to determine if an array has duplicate elements by comparing its length to the length of a set created from it.
• Write a Python program to iterate over an array and use a set to track seen items, returning True if a duplicate is found.
• Write a Python program to implement a function that returns True if any element appears more than once in an array using collections.Counter.
• Write a Python program to use a loop to check for duplicates in an array without using built-in functions.

Python Code Editor:

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