Python: Remove all instances of a given value from a given array of integers and find the length of the new array

Last update on April 17 2025 13:05:34 (UTC/GMT +8 hours)

Remove Value from Array

Write a Python program to remove all instances of a given value from a given array of integers and find the length of the newly created array.

Sample Solution:

Python Code:

# Define a function to remove elements equal to a given value from a list
def remove_element(array_nums, val):
    # Initialize a variable to iterate through the list
    i = 0
    
    # Iterate through the list
    while i < len(array_nums):
        # Check if the current element is equal to the given value
        if array_nums[i] == val:
            # Remove the element if it matches the given value
            array_nums.remove(array_nums[i])
        else:
            # Move to the next index if the elements do not match
            i += 1
    
    # Return the length of the modified list
    return len(array_nums)

# Test the function with different lists and values, and print the results
print(remove_element([1, 2, 3, 4, 5, 6, 7, 5], 5))    
print(remove_element([10, 10, 10, 10, 10], 10))       
print(remove_element([10, 10, 10, 10, 10], 20))       
print(remove_element([], 1))    

Sample Output:

6
0
5
0

Explanation:

Here is a breakdown of the above Python code:

• The function "remove_element()" removes elements equal to a given value from a list.
• It initializes a variable 'i' to iterate through the list.
• It iterates through the list using a while loop.
• If the current element is equal to the given value, it removes that element from the list.
• If the elements do not match, it moves to the next index.
• The function returns the length of the modified list.
• Test the function with different lists and values, and print the results.

Visual Presentation:

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python program to remove all instances of a given value from an array and return the new length.
• Write a Python program to filter out a target value from a list and count the number of remaining elements.
• Write a Python program to create a new list excluding all occurrences of a specified integer.
• Write a Python program to modify an array in-place by eliminating a given value and updating the list length accordingly.

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Python Code Editor:

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