Program to Check Balanced of Parenthesis in Python

July 5, 2022

Check the balance of parenthesis in Python

To check balanced parenthesis is a basic interview question where we are asked to find whether the given string(of brackets) is balanced or not. To do this , the traditional way of doing is using stacks but we can also find by using normal programming techniques. Different brackets are ( ) , [ ] , { }. Question can be asked on any type of bracket or of all types of brackets.

Missing Braces Program in Python Working:

Step 1: Take the input string
Step 2: Call the isbalanced function
Step 3: This function returns True if the string is balanced, else False
Step 4: This function returns true or false for the string that contains ( )

Python code:- Check the balance of parenthesis in Python

Run

def isbalanced(s):
  c= 0
  ans=False
  for i in s:
    if i == "(": 
     c += 1
    elif i == ")":
     c-= 1
    if c < 0:
     return ans
    if c==0:
     return not ans
  return ans
s="{[]}"
print("Given string is balanced :",isbalanced(s))

Given string is balanced : True

Working:

This approach is to check whether the string is balanced or not in case the string contains several types of brackets like { ( [ ] ) }

Step 1: Take the input string
Step 2: Call the isbalanced function
Step 3: This function returns True if string is balanced , else False
Step 4: This function replaces the set of brackets until the string len becomes zero

Solution 2:

Run

def isbalanced(s):
    while(len(s)!=0):
        s=s.replace('()','')
        s=s.replace('[]','')
        s=s.replace('{}','')
    if(len(s)==0):
        return True
    else:
        return False
s=input("Enter a string of brackets:")
print("Given string is balanced:",isbalanced(s))

Enter a string of brackets: ({{}}){}[]
Given string is balanced : True