Python Program to Reverse String Using Stack

Reverse a string using stack in python; Through this tutorial, i am going to show you how to reverse a string using stack in python.

In this tutorial, i will write a program to reverse a string using stack in python.

Python Program to Reverse String Using Stack

Use the following steps and write a python program to reverse string using stack;

• Get input string in program from user.
• Read string from left to right and push each string element/character in stack.
• Once the string reading is done.
• Pop each string character/element one by one and put them back to the string.
• Once the stack is empty return the result in string form.
• Print reverse a string.

class  Stack_to_reverse  :
    # Creates  an  empty  stack.
    def	__init__(  self  ):
        self.items  =  list()
        self.size=-1
    #Returns  True  if  the  stack  is  empty  or  False  otherwise.
    def  isEmpty(  self  ):
        if(self.size==-1):
            return True
        else:
            return False
    # Removes  and  returns  the  top  item  on  the  stack.
    def  pop(  self  ):
        if  self.isEmpty():
            print("Stack is empty")
        else:
            return self.items.pop()
            self.size-=1
    # Push  an  item  onto  the  top  of  the  stack.
    def  push(  self,  item  ):
        self.items.append(item)
        self.size+=1
    def reverse(self,string):
        n = len(string)
 # Push all characters of string to stack
        for i in range(0,n):
            S.push(string[i])
 # Making the string empty since all characters are saved in stack
        string=""
 # Pop all characters of string and put them back to string
        for i in range(0,n):
            string+=S.pop()
        return string
S=Stack_to_reverse()
seq=input("Enter a string to be reversed")
sequence = S.reverse(seq)
print("Reversed string is " + sequence)

After executing the program, the output will be:

Enter a string to be reversed hello
Reversed string is olleh

Recommended Python Tutorials