C Program to Convert a Number Decimal System to Binary System using Recursion

The following C program using recursion finds a binary equivalent of a decimal number entered by the user. The user has to enter a decimal which has a base 10 and this program evaluates the binary equivalent of that decimal number with base 2.

Here is the source code of the C program to find the binary equivalent of the decimal number. The C program is successfully compiled and run on a Linux system. The program output is also shown below.

1. /*

2.  * C Program to Convert a Number Decimal System to Binary System using Recursion

3.  */

4. #include <stdio.h>

6. int convert(int);

8. int main()

9. {

10.     int dec, bin;

12.     printf("Enter a decimal number: ");

13.     scanf("%d", &dec);

14.     bin = convert(dec);

15.     printf("The binary equivalent of %d is %d.\n", dec, bin);

17.     return 0;

18. }

20. int convert(int dec)

21. {

22.     if (dec == 0)

23.     {

24.         return 0;

25.     }

26.     else

27.     {

28.         return (dec % 2 + 10 * convert(dec / 2));

29.     }

30. }

$ cc pgm31.c
$ a.out
Enter a decimal number: 10
The binary equivalent of 10 is 1010.