Fibonacci Number Benchmarks

fib.cc

// g++ (GCC) 4.4.7 20120313 (Red Hat 4.4.7-4)

#include <iostream>
#include <cstdlib>

unsigned fib(unsigned n) {
  if (n < 2) {
    return n;
  } else {
    return fib(n - 2) + fib(n - 1);
  }
}

int main(int argc, char **argv) {
  unsigned n = atoi(argv[1]);
  unsigned ret = fib(n);
  std::cout << "fib(" << n << ") = " << ret << std::endl;
  return 0;
}

// $ g++ -O3 fib.cc -o fib
//
// $ time ./fib 1
// fib(1) = 1
// 
// real    0m0.002s
// user    0m0.001s
// sys     0m0.001s
//
// $ time ./fib 40
// fib(40) = 102334155
// 
// real    0m0.458s
// user    0m0.456s
// sys     0m0.000s

fib.erl

%% Erlang/OTP 17 [erts-6.1] 

-module(fib).

-export([fib/1]).

-compile([native, {hipe, [o3]}]).

-spec fib(non_neg_integer()) -> non_neg_integer().
fib(N) when N < 2 -> N;
fib(N)            -> fib(N - 2) + fib(N - 1).

%% $ erl
%%
%% > c(fib).
%% {ok, fib}
%% 
%% > timer:tc(fun () -> fib:fib(40) end).
%% {1175278,102334155}  % 1.175 seconds

fib.go

// go version go1.3 linux/amd64

package main

func fib(n uint32) uint32 {
        if n < 2 { return n } else { return fib(n - 2) + fib(n - 1)}
}

fib.lisp

;; SBCL 1.2.1

(declaim (inline fib))
(defun fib (n)
  (declare (optimize (speed 3) (safety 0))
           (fixnum n))
  (if (< n 2)
      n
    (the fixnum (+ (fib (- n 2)) (fib (- n 1))))))

(time (fib 40))

Evaluation took:
  0.772 seconds of real time
  0.772883 seconds of total run time (0.771883 user, 0.001000 system)
  100.13% CPU
  2,081,064,538 processor cycles
  0 bytes consed

102334155

fib_test.go

package main

import "testing"

func BenchmarkFib(b *testing.B) {
        for i := 0; i < b.N; i += 1 {
                fib(40)
        }
}

// go test -bench .
// testing: warning: no tests to run
// PASS
// BenchmarkFib           2         841112488 ns/op  // 0.841 seconds
// ok      _/home/ohta/dev/bench   2.535s