Python: Separate parentheses groups

Last update on March 22 2025 13:47:33 (UTC/GMT +8 hours)

Split Matched Parentheses Groups

Given a string consisting of whitespace and groups of matched parentheses, write a Python program to split it into groups of perfectly matched parentheses without any whitespace.

Input: 
( ()) ((()()())) (()) ()
Output:
['(())', '((()()()))', '(())', '()']

Input:
() (( ( )() (   )) ) ( ())
Output:
['()', '((()()()))', '(())']

Sample Solution:

Python Code:

# Define a function named 'test' that separates parentheses groups from a combined string
def test(combined):
    # Initialize an empty list 'ls' to store separate parentheses groups
    ls = []
    
    # Initialize an empty string 's2' to build each parentheses group
    s2 = ""
    
    # Iterate through each character in the combined string (ignoring spaces)
    for s in combined.replace(' ', ''):
        # Append the character to 's2'
        s2 += s
        
        # Check if the count of "(" equals the count of ")"
        if s2.count("(") == s2.count(")"):
            # Append the current parentheses group to the list 'ls'
            ls.append(s2)
            
            # Reset 's2' for the next parentheses group
            s2 = ""
    
    # Return the list of separate parentheses groups
    return ls

# Example 1
combined1 = '( ()) ((()()())) (()) ()'
print("Parentheses string:")
print(combined1)
print("Separate parentheses groups of the said string:")
print(test(combined1))

# Example 2
combined2 = '() (( ( )() (   )) ) ( ())'
print("\nParentheses string:")
print(combined2)
print("Separate parentheses groups of the said string:")
print(test(combined2))

Sample Output:

Parentheses string:
( ()) ((()()())) (()) ()
Separate parentheses groups of the said string:
['(())', '((()()()))', '(())', '()']

Parentheses string:
() (( ( )() (   )) ) ( ())
Separate parentheses groups of the said string:
['()', '((()()()))', '(())']

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python program to split a string into groups of perfectly matched parentheses by removing whitespace.
• Write a Python program to use a stack to partition a string of nested parentheses into separate balanced groups.
• Write a Python program to implement a regular expression that captures groups of matched parentheses without extra spaces.
• Write a Python program to iterate over a string and extract each valid group of nested parentheses as a separate element.

Python Code Editor :

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