C++ Exercises: Find the sum of first and last digit of a number

Last update on April 07 2025 13:01:12 (UTC/GMT +8 hours)

57. Sum of First and Last Digits of a Number

Write a program in C++ to find the sum of the first and last digits of a number.

Visual Presentation:

C++ Exercises: Find the sum of first and last digit of a number

Sample Solution:

C++ Code :

#include <iostream> // Include the input/output stream library
using namespace std; // Using standard namespace

int main() // Main function where the execution of the program starts
{
    int n, first, last, sum; // Declare integer variables n, first, last, and sum

    // Display message asking for input
    cout << "\n\n Find the sum of first and last digit of a number:\n";
    cout << "------------------------------------------------------\n";
    cout << " Input any number: ";
    cin >> n; // Read input for the number from the user

    first = n; // Assign the input number to the variable 'first'
    last = n % 10; // Calculate the last digit of the number

    for (first = n; first <= 10; first = first / 10); // Loop to find the first digit of the number

    // Display the first and last digit of the number
    cout << " The first digit of " << n << " is: " << first << endl;
    cout << " The last digit of " << n << " is: " << last << endl;

    // Calculate and display the sum of the first and last digit of the number
    cout << " The sum of first and last digit of " << n << " is: " << first + last << endl;
}

Sample Output:

 Find the sum of first and last digit of a number:                     
------------------------------------------------------                 
 Input any number: 12345                                               
 The first digit of 12345 is: 1                                        
 The last digit of 12345 is: 5                                         
 The sum of first and last digit of 12345 is: 6

Flowchart:

For more Practice: Solve these Related Problems:

Write a C++ program to calculate the sum of the first and last digits of an integer by extracting digits using division and modulus.
Write a C++ program that reads a number and prints the sum of its first and last digits computed without converting the number to a string.
Write a C++ program to obtain the first digit by iterating until the number is less than 10, and add it to the last digit.
Write a C++ program that computes and displays the sum of the boundary digits of an input number using arithmetic operations.

C++ Code Editor:

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