more e2 versions

e2/e2.cs

@@ -0,0 +1,14 @@
+using System;
+
+public class E2 {
+	public static void Main() {
+		int sum, last, current, tmp;
+		last = 0;
+		sum = 0;
+		for (current = 1; current < 4000000; tmp = current, current += last, last = tmp) {
+			if (current % 2 == 0)
+				sum += current;
+		}
+		System.Console.WriteLine(sum);
+	}
+}

e2/e2.erl

@@ -0,0 +1,8 @@
+-module(e2).
+-export([e2/0, fib_count/4]).
+
+fib_count(Last, Current, Max, Sum) when Current >= Max -> Sum;
+fib_count(Last, Current, Max, Sum) when Current rem 2 == 0 -> fib_count(Current, Last + Current, Max, Sum + Current);
+fib_count(Last, Current, Max, Sum) -> fib_count(Current, Last + Current, Max, Sum).
+
+e2() -> fib_count(0, 1, 4000000, 0).

e2/e2.m

@@ -0,0 +1 @@
+#include <objc/Object.h>

e2/e2.pl

@@ -0,0 +1,5 @@
+fib_count(Last, Current, Max, Sum, Sum) :- Current >= Max.
+fib_count(Last, Current, Max, Acc, Sum) :- 0 is Current rem 2, Next is Last + Current, NewAcc is Acc + Current, fib_count(Current, Next, Max, NewAcc, Sum).
+fib_count(Last, Current, Max, Acc, Sum) :- Next is Last + Current, fib_count(Current, Next, Max, Acc, Sum).
+
+e2(Result) :- fib_count(0, 1, 4000000, 0, Result).