Thread: Need suggestion with Hexadecimal to Binary converter.

Code:

#include<stdio.h>#define MAX 1000


int main(){
    char binaryNumber[MAX],hexaDecimal[MAX];
    long int i=0;


    printf("Enter any hexadecimal number: ");
    scanf("%s",hexaDecimal);


    printf("\nEquivalent binary value: ");
    while(hexaDecimal[i]){
         switch(hexaDecimal[i]){
             case '0': printf("0000"); break;
             case '1': printf("0001"); break;
             case '2': printf("0010"); break;
             case '3': printf("0011"); break;
             case '4': printf("0100"); break;
             case '5': printf("0101"); break;
             case '6': printf("0110"); break;
             case '7': printf("0111"); break;
             case '8': printf("1000"); break;
             case '9': printf("1001"); break;
             case 'A': printf("1010"); break;
             case 'B': printf("1011"); break;
             case 'C': printf("1100"); break;
             case 'D': printf("1101"); break;
             case 'E': printf("1110"); break;
             case 'F': printf("1111"); break;
             case 'a': printf("1010"); break;
             case 'b': printf("1011"); break;
             case 'c': printf("1100"); break;
             case 'd': printf("1101"); break;
             case 'e': printf("1110"); break;
             case 'f': printf("1111"); break;
             default:  printf("\nInvalid hexadecimal digit %c ",hexaDecimal[i]); return 0;
         }
         i++;
    }


    return 0;
}

So this is my current code, is there anyway I can reduce the size and use a main function to ask for input and a call function to do all the conversion and return it? I am confused for the past few days trying to figure it out and finally ended up here. Anyway can I write it as a something like this

Code:

int main()
{
//ask for user input hexadecimal into here and call a let's say hex2binary() function
}

int hex2binary(...)
{
//an array with dynamic memory, malloc? and convert it and return values
}

Any suggestion appreciated, I don't really need the full code, just a simple instruction on how and where to start. Thanks!