Implement function bin2dec that takes a binary number bin_num as a string argument and prints out the corresponding decimal number. Each char in the string has a value of either '0' or '1' to represent a bit. The string does not have any leading space. For example, function call bin2dec("1011") should print 11. You can assume that bin_num can have up to 32 bits. To convert a char in the binary number string to an int, you can subtract the char by '0'. For example, you can use bin_num[0] - '0' to get the int value of the most significant bit of the binary number. Restriction: printf is the ONLY C library function that you can use in the implementation.