C++ Exercises: Swap first and last digits of any number

C++ Basic: Exercise-61 with Solution

Swap First and Last Digit

Write a C++ program to swap the first and last digits of any number.

Sample Solution:

C++ Code :

#include <iostream> // Including input-output stream header file
#include <math.h>   // Including math functions header file
using namespace std; // Using the standard namespace

int main() { // Start of the main function
    int n, first, last, sum, digits, nn, a, b; // Declaration of integer variables

    cout << "\n\n Find the number after swapping the first and last digits:\n"; // Displaying program's purpose
    cout << "-------------------------------------------------------------\n";
    cout << " Input any number: ";
    cin >> n; // Taking input from the user

    digits = (int)log10(n); // Calculating the number of digits in the number

    // Extracting the first and last digits of the number
    first = n / pow(10, digits); // Getting the first digit
    last = n % 10; // Getting the last digit

    // Swapping the first and last digits
    a = first * (pow(10, digits)); // Multiplying the first digit by a power of 10
    b = n % a; // Getting the remaining digits after removing the first digit
    n = b / 10; // Removing the last digit

    // Constructing the new number after swapping
    nn = last * (pow(10, digits)) + (n * 10 + first); // Constructing the new number

    cout << " The number after swapping the first and last digits is: " << nn << endl; // Displaying the result
}

Sample Output:

Find the number after swapping the first and last digits:             
-------------------------------------------------------------          
 Input any number: 12345                                               
 The number after swaping the first and last digits are: 52341 

Flowchart:

C++ Code Editor:

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