01  #include<stdio.h>
02  #define MAX 1000
03  
04  int main()
05  {
06   char hexaDecimal[MAX];
07   long int i=0;
08  
09   printf("Enter any hexadecimal number: ");
10   gets(hexaDecimal);
11  
12   printf("nEquivalent binary value: ");
13  
14   while(hexaDecimal[i])
15   {
16    switch(hexaDecimal[i])
17    {
18     case '0': printf("0000"); break;
19     case '1': printf("0001"); break;
20     case '2': printf("0010"); break;
21     case '3': printf("0011"); break;
22     case '4': printf("0100"); break;
23     case '5': printf("0101"); break;
24     case '6': printf("0110"); break;
25     case '7': printf("0111"); break;
26     case '8': printf("1000"); break;
27     case '9': printf("1001"); break;
28  
29     case 'A':
30     case 'a': printf("1010"); break;
31  
32     case 'B':
33     case 'b': printf("1011"); break;
34  
35     case 'C':
36     case 'c': printf("1100"); break;
37  
38     case 'D':
39     case 'd': printf("1101"); break;
40  
41     case 'E':
42     case 'e': printf("1110"); break;
43  
44     case 'F':
45     case 'f': printf("1111"); break;
46  
47     default:  printf("nInvalid hexadecimal digit %c ",hexaDecimal[i]);
48     return;
49  
50    }
51    i++; // loop increment
52   }
53  return 0;
54  }

 
 OUTPUT :
 
 Enter any hexadecimal number : 1AC
 Equivalent binary value : 000110101100