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FizzBuzz - C

Continuing on from my ruby example, I’ve implemented Fizz Buzz in C so we can compare the differences. Hopefully, by comparing the C version withe ruby example we’ll level up a little on software craftmanship.

Here is an example implementation in C:

#include "stdio.h"

int main ()
    for(int i = 1; i<=25; i++)
        if ((i%3 == 0) && (i%5 == 0)) printf("FizzBuzz");
        else if (i%3==0) printf("Fizz");
        else if (i%5==0) printf("Buzz");
        else printf("%d",i);
    return (0);

Stepping thru this code, we see the program does the following:

  • Includes a header file so we have access to the printf function
  • Loops thru the numbers between 1 and 25
  • Prints ‘FizzBuzz’ if the number is evenly divisable by 3 and 5
  • Or, it prints ‘Fizz’ if the number is evenly divisable by 3, and not 5
  • Or, it prints ‘Buzz’ if the number is evenly divisable by 5, and not 3
  • Or, it just prints the number
  • Regardless, it allways prints a newline via the ‘\n’ character

Note: I’m working on OSX.

Now, lets take another look at our ruby example:

1.upto(25) do |x|
  output = nil
  output = output.to_s + 'Fizz' if x % 3 == 0
  output = output.to_s + 'Buzz' if x % 5 == 0
  puts output || x

Now that we’ve seen them both, lets discuss some takeaways:

  • The ruby version doesn’t require a build step.
  • The ruby version has many useful functions, such as ‘upto’, that make it more readable.
  • The C version is faster.

The C version is faster? Where’s the proof?

Good question. If we ran the code in question for a larger number, say 100,000, and time the results, we get:


time ./ruby1.rb

real	0m0.513s
user	0m0.249s
sys	0m0.155s


> time ./c1

real	0m0.170s
user	0m0.044s
sys	0m0.053s

Remember, since Ruby is built in C, this shouldn’t be surprising. Its turtles all the way down.

That’s it for now. Stay tuned for more analysis.