Write a program to check duplicate values ​​in Python

Topic : Check if an array or any data structure has duplicate values. A duplicate value is a value that occurs at least twice in an array or in a list or data structure.

Example :

Input: [1, 2, 3, 1] Output: True

In this article, TipsMake.com will learn with you how to write a program to check duplicate values ​​in Python programming language.

Write a program to check duplicate values ​​in Python

To write a duplicate value checker program in Python, we need to declare a Python function that can take a list of values ​​of any data type. Here is the sample code of the duplicate value checker program in Python:

def containsDuplicate(nums): for i in range(len(nums)): for j in range(i + 1, len(nums)): if nums[i] == nums[j]: return True else: return False nums = [1,2,3,1] print(containsDuplicate(nums))

The returned result is:

True

The function above works like this:

1. A loop is run from the first position (i) to the last position of the array.
2. Another loop is run from position j = i + 1 to the end of the array.
3. If the number at position i is equal to the number at position j, return True.
4. Otherwise, return False.

You can use this Python function for any data type.

Conclude

Checking for duplicates in an array or in any data structure is one of the common interview questions. In interviewing or testing candidates' qualifications, you need to use an algorithm to solve this problem.

TipsMake.com hopes that this article will be useful to you.

Kareem Winters

Update 07 July 2023