(i) If a four-digit number is input through the keyboard, write a program to obtain the sum of the first and last digit of this number.

/* This program takes a four-digit integer from user, and shows sum of first and last digit.*/

#include<stdio.h>

#include<conio.h>

int main ()

{

/*Declaring and initializing variables*/

    int value,dig1,dig2,dig3,dig4,sum;

/*prompt to take the input*/

    printf("Please enter a foure-digit number: ");

/*Taking input*/   

    scanf("%d",&value);

/*Calculations*/

    dig1 = value % 10;

  

    /* e.g. if value is 12345 then 12345 % 10 gives 5*/

  

    value = value / 10;

  

    /* '12345/10' gives '1234.5' but this is integer division so digit/s after '.' will

    be dropped and we get '1234'*/

   

    dig2 = value % 10;

  

    /*now '1234 % 10' gives '4' and so on*/

    value = value / 10;

    dig3 = value % 10;

    value = value / 10;

    dig4 = value % 10;

   

   

    sum = dig4 + dig1;

/*showing Results*/   

    printf("\n   Solution: ");

    printf("\n   __________");

    printf("\n\n   Sum of %d and %d is: %d",dig4,dig1,sum);

    getch();

    return 0;

}