Write a Python program to Reverse String using For Loop, while loop, and Functions with an example.
Reverse String using For Loop
This program allows the user to enter any sentence. Next, this code reverses the string using For Loop.
st1 = input("Please enter your own : ") st2 = '' for i in st1: st2 = i + st2 print("\nOriginal = ", st1) print("After = ", st2)
Please enter your own : Coding Original = Coding After = gnidoC
You can observe from the above program screenshot that word is Coding.
For Loop First Iteration: for i in st1
=> for C in Coding
str2 = C + st2=> C + ”
Second Iteration: for o in Coding
st2 = o + C => oC
Python Program to reverse a String using While Loop
This program using the while loop is the same as above. However, we just replaced the For Loop with While Loop. Here, the len function is used to find the length of the total characters in a sentence.
# using a while loop a = input("Please enter your own : ") b = '' i = len(a) - 1 while(i >= 0): b = b + a[i] i = i - 1 print("\nThe Original = ", a) print("The Inverted = ", b))
Please enter your own : Tutorial Gateway The Original = Tutorial Gateway The Inverted = yawetaG lairotuT
It is another way of reversing a string using functions.
def StrInverse(str1): str2 = str1[::-1] return str2 a = input("Please enter your own : ") b = StrInverse(a) print("\nOriginal = ", a) print("After = ", b)
Please enter your own : Hello World! Original = Hello World! After = !dlroW olleH
We are doing string reverse in this code by calling the function recursively.
# using recursive function def StrInverted(str1): if(len(str1) == 0): return str1 else: return StrInverted(str1[1:]) + str1 str2 = input("Please enter your own : ") str3 = StrInverted(str2) print("\nThe Original = ", str2) print("The Inversed = ", str3)