new language: Erlang

run.sh

@@ -156,5 +156,12 @@ echo "*------------ R -------------*"
 sleep 5 # cpu cool down
 
 Rscript ./src/prime.R
-echo "" 
+echo ""
 
+echo "*-------------- erlang ---------------*"
+erl -eval 'erlang:display(erlang:system_info(otp_release)), halt().' -noshell
+erlc -o src ./src/prime.erl
+erl -pa src -noshell -s prime main -s init stop
+
+rm ./src/prime.beam
+echo ""

src/prime.erl

@@ -0,0 +1,30 @@
+-module(prime).
+-export([is_prime/1, main/0]).
+
+is_prime(N) when N =< 1 ->
+    false;
+is_prime(N) ->
+    is_prime_helper(N, 2, round(math:sqrt(N))).
+
+is_prime_helper(_, I, End) when I > End ->
+    true;
+is_prime_helper(N, I, End) ->
+    case N rem I of
+        0 -> false;
+        _ -> is_prime_helper(N, I + 1, End)
+    end.
+
+main() ->
+    Start = erlang:system_time(millisecond),
+    C = count_primes(0, 9000000, 0),
+    io:format("~p~n", [C]),
+    End = erlang:system_time(millisecond),
+    io:format("~pms~n", [End - Start]).
+
+count_primes(I, Max, C) when I < Max ->
+    case is_prime(I) of
+        true -> count_primes(I + 1, Max, C + 1);
+        false -> count_primes(I + 1, Max, C)
+    end;
+count_primes(_, _, C) ->
+    C.