Count occurrences of a value

Easy

≈ 8 minute session

Summary

Count how many times a target value appears in an array.

Problem statement

Given a list arr and a target value val, return the number of times val appears in arr. The function should work for any Python object (ints, strings, None, etc.). Time complexity O(n).

Task

Create a function that returns the number of occurrences of a given value in a list. Practice equality checks and iteration.

Examples

Basic example

Input

arr = [1, 2, 2, 3, 2], val = 2

Output

Explanation

2 appears three times in the list.

Input format

Two arguments: (list, value). Example: ([1,2,3,2], 2)

Output format

An integer count of how many times value occurs in the list.

Constraints

List length 0..10^6. Equality check uses Python's ==. Time O(n).

Samples

Sample input 0

["a", "b", "a"], "a"

Sample output 0

Explanation 0

"a" appears twice.

Code editor

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03:49 PM

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