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convert Decimal to Hexadecimal number system

convert Decimal to Hexadecimal number system

Write a C program to input decimal number from user and convert to Hexadecimal number system. How to convert Decimal to Hexadecimal number system in C programming.

Decimal number system
Decimal number system is a base 10 number system. Decimal number system uses 10 symbols to represent all number i.e. 0123456789

Hexadecimal number system
Hexadecimal number system is a base 16 number system. Hexadecimal number system uses 16 symbols to represent all numbers i.e. 0123456789ABCDEF


Algorithm to convert decimal to hexadecimal number system

Algorithm Conversion from Decimal to Hexadecimal
begin:
    read (decimal);
    hex = NULL; rem = 0;
    HEXVALUES[] = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F;
    While(decimal != 0)
        begin:
            rem = decimal % 16;
            hex = hex + HEXVALUES[rem];
            decimal = decimal / 16;
        end;
    Reverse(hex);
    print('Hexadecimal = ' hex);
end;

#include <stdio.h>
#include <string.h>

int main()
{
    char HEXVALUE[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};

    long long decimal, tempDecimal;
    char hex[65];
    int index, rem;
    
    /* Input decimal number from user */
    printf("Enter any decimal number: ");
    scanf("%lld", &decimal);
    tempDecimal = decimal;

    index = 0;
    
    /* Decimal to hexadecimal conversion */
    while(tempDecimal !=0)
    {
        rem = tempDecimal % 16;

        hex[index] = HEXVALUE[rem];

        tempDecimal /= 16;

        index++;
    }
    hex[index] = '\0';

    strrev(hex);

    printf("\nDecimal number = %lld\n", decimal);
    printf("Hexadecimal number = %s", hex);

    return 0;
}