Reverse Digits of a Number

Reverse the digits of an integer using a loop.

PythonBeginner

Python

# Program to reverse digits of a number

num = int(input("Enter an integer: "))

rev = 0
temp = abs(num)

while temp > 0:
    digit = temp % 10
    rev = rev * 10 + digit
    temp //= 10

if num < 0:
    rev = -rev

print("Reversed number is", rev)

Output

Enter an integer: 1234
Reversed number is 4321

We build the reversed number by shifting previous digits left (×10) and adding the current last digit each iteration.

Sum of Digits

Calculate Factorial (Loop)