Program to Swap First and Last Digit of a Number using While loop
- Write a program to Swap First and Last Digit of a Number using While loop in C
- Write a program to Swap First and Last Digit of a Number using While loop in C++
- Write a program to Swap First and Last Digit of a Number using While loop in Python
- Write a program to Swap First and Last Digit of a Number using While loop in PHP
- Write a program to Swap First and Last Digit of a Number using While loop in Java
- Write a program to Swap First and Last Digit of a Number using While loop in Java Script
- Write a program to Swap First and Last Digit of a Number using While loop in C#
Explanation:
To swap the first and last digits of a number using a While loop, follow this approach:
Steps:
- Extract the last digit: Use the modulo operation (n % 10).
- Extract the first digit: Repeatedly divide the number by 10 until only one digit remains.
- Remove the first and last digits: Construct a new number by removing the first and last digits and place the swapped digits in their respective positions.
- Rebuild the number: Create a new number by placing the last digit at the front and the first digit at the end.
Logic:
- Take input for the number (n).
- If the number has only one digit, there’s no need to swap.
- Get the last digit using n % 10.
- Get the first digit by dividing the number by 10 repeatedly until the result is less than 10.
- Remove the first and last digits from the number.
- Rebuild the number with the first and last digits swapped.
Program to Swap First and Last Digit of a Number using While loop
-
C
-
C++
-
Python
-
PHP
-
JAVA
-
Java Script
-
C#
#include <stdio.h>
int main() {
int num, first_digit, last_digit, digits = 0, temp;
printf("Enter a number: ");
scanf("%d", &num);
// Handle negative numbers
if (num < 0) {
num = -num;
}
temp = num;
// Find number of digits
while (temp != 0) {
digits++;
temp /= 10;
}
// Find last digit
last_digit = num % 10;
// Find first digit
first_digit = num;
while (first_digit >= 10) {
first_digit /= 10;
}
// Remove first and last digits from the number
num = num - first_digit * pow(10, digits - 1);
num = num + last_digit * pow(10, digits - 1);
num = num - last_digit + first_digit;
printf("Number after swapping first and last digit: %d\n", num);
return 0;
}
#include <iostream>
#include <cmath>
using namespace std;
int main() {
int num, first_digit, last_digit, digits = 0, temp;
cout << "Enter a number: ";
cin >> num;
// Handle negative numbers
if (num < 0) {
num = -num;
}
temp = num;
// Find number of digits
while (temp != 0) {
digits++;
temp /= 10;
}
// Find last digit
last_digit = num % 10;
// Find first digit
first_digit = num;
while (first_digit >= 10) {
first_digit /= 10;
}
// Remove first and last digits from the number
num = num - first_digit * pow(10, digits - 1);
num = num + last_digit * pow(10, digits - 1);
num = num - last_digit + first_digit;
cout << "Number after swapping first and last digit: " << num << endl;
return 0;
}
num = int(input("Enter a number: "))
# Handle negative numbers
if num < 0:
num = -num
# Convert to string to easily manipulate digits
num_str = str(num)
# Get first and last digits
first_digit = int(num_str[0])
last_digit = int(num_str[-1])
# Swap first and last digits
if len(num_str) > 1:
num_str = str(last_digit) + num_str[1:-1] + str(first_digit)
else:
num_str = str(first_digit)
print(f"Number after swapping first and last digit: {num_str}")
<?php
$num = (int)readline("Enter a number: ");
// Handle negative numbers
if ($num < 0) {
$num = -$num;
}
$num_str = strval($num);
// Get first and last digits
$first_digit = intval($num_str[0]);
$last_digit = intval($num_str[strlen($num_str) - 1]);
// Swap first and last digits
if (strlen($num_str) > 1) {
$num_str = $last_digit . substr($num_str, 1, strlen($num_str) - 2) . $first_digit;
} else {
$num_str = $first_digit;
}
echo "Number after swapping first and last digit: $num_str\n";
?>
import java.util.Scanner;
public class SwapFirstLast {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number: ");
int num = sc.nextInt();
// Handle negative numbers
if (num < 0) {
num = -num;
}
String numStr = Integer.toString(num);
// Get first and last digits
int firstDigit = Character.getNumericValue(numStr.charAt(0));
int lastDigit = Character.getNumericValue(numStr.charAt(numStr.length() - 1));
// Swap first and last digits
if (numStr.length() > 1) {
numStr = lastDigit + numStr.substring(1, numStr.length() - 1) + firstDigit;
} else {
numStr = Integer.toString(firstDigit);
}
System.out.println("Number after swapping first and last digit: " + numStr);
sc.close();
}
}
let num = parseInt(prompt("Enter a number: "));
// Handle negative numbers
if (num < 0) {
num = -num;
}
let numStr = num.toString();
// Get first and last digits
let firstDigit = parseInt(numStr[0]);
let lastDigit = parseInt(numStr[numStr.length - 1]);
// Swap first and last digits
if (numStr.length > 1) {
numStr = lastDigit + numStr.slice(1, numStr.length - 1) + firstDigit;
} else {
numStr = firstDigit.toString();
}
console.log(`Number after swapping first and last digit: ${numStr}`);
using System;
class Program {
static void Main() {
Console.Write("Enter a number: ");
int num = int.Parse(Console.ReadLine());
// Handle negative numbers
if (num < 0) {
num = -num;
}
string numStr = num.ToString();
// Get first and last digits
int firstDigit = int.Parse(numStr[0].ToString());
int lastDigit = int.Parse(numStr[numStr.Length - 1].ToString());
// Swap first and last digits
if (numStr.Length > 1) {
numStr = lastDigit + numStr.Substring(1, numStr.Length - 2) + firstDigit;
} else {
numStr = firstDigit.ToString();
}
Console.WriteLine($"Number after swapping first and last digit: {numStr}");
}
}