diff --git a/dqn.jl b/dqn.jl
index e3b17dcca9be50fe78cfaa05ca6a8fc5ec6aca33..82c979aad95e8c1a5cd683b041da5e08cbdf8f78 100644
--- a/dqn.jl
+++ b/dqn.jl
@@ -111,8 +111,10 @@ function collect_episode(ep, max_size=1000)
     rewards = Float64[]
     actions = Int[]
     raw_frames = Array{Float64,2}(100800,max_size+1)
-    local s1, i
-    for (i,(s,a,r,s1)) in take(enumerate(ep), max_size)
+    local s1
+    i = 0
+    for (s,a,r,s1) in take(ep, max_size)
+        i += 1
         raw_frames[:,i] = s
         if (i-1) % action_repeat == 0
             push!(rewards, r)