program to convert decimal number into Hexadecimal.

//program to convert decimal number into Hexadecimal.
#include<stdio.h>
#include<conio.h>

void main()

{

  long int decimal_number;

  printf("Enter any decimal number: ");

  scanf("%ld",&decimal_number);

  printf("Equivalent hexadecimal number is: %X",decimal_number);

getch();

}

logics in mind:

if decimal number is 19 (base 10) then
^{hexadecimal number can be obtained using simply its format specifier %x.
       note:}

we can also write same program using ascii value and array.
the program goes like,

#include<stdio.h>

void main()

{

    long int decimalNumber,remainder,quotient;

    int i=1,j,temp;

    char hexadecimalNumber[100];                    //array is used to store equivalent hexadecimal number

    printf("Enter any decimal number: ");

    scanf("%ld",&decimalNumber);

    quotient = decimalNumber;

    while(quotient!=0){

         temp = quotient % 16;

      //To convert integer into character

      if( temp < 10)

           temp =temp + 48;          //48 is added to temp to convert number into character, look ascii table

      else

         temp = temp + 55;                                //ascii value is used as a character after adding to number

      hexadecimalNumber[i++]= temp;

      quotient = quotient / 16;

  }

    printf("Equivalent hexadecimal value of decimal number %d: ",decimalNumber);

    for(j = i -1 ;j> 0;j--)

      printf("%c",hexadecimalNumber[j]);

}

                                        source:
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