diff --git a/day7.hs b/day7.hs
index d3fb642..45ce054 100644
--- a/day7.hs
+++ b/day7.hs
@@ -36,10 +36,10 @@ prepareAmps (p1:p2:p3:p4:p5:_) software = do
 part2 :: [Amplifier] -> Int
 part2 amps = do
         let ampA = link (amps!!4) (amps!!0) 
-        let ampB = link (amps!!0) (amps!!1)  
-        let ampC = link (amps!!1) (amps!!2) 
-        let ampD = link (amps!!2) (amps!!3) 
-        let ampE = link (amps!!3) (amps!!4)  
+        let ampB = link (ampA) (amps!!1)  
+        let ampC = link (ampB) (amps!!2) 
+        let ampD = link (ampC) (amps!!3) 
+        let ampE = link (ampD) (amps!!4)  
 	if state ampE == [88]  
                then head (output (amps!!4))
                else part2 [ampA,ampB,ampC,ampD,ampE] 	
@@ -64,40 +64,42 @@ calcthrusters software (p1:p2:p3:p4:p5:_) start = do
 
 
 operation :: [Int] -> [Int] -> Int -> [Int] -> [Int] -> Amplifier
-operation (99:_) state index input output = 
-          Amplifier state index input output
-operation (op:x:y:z:_) state index input output 
+operation (99:_) state i input output = 
+          Amplifier state i input []
+operation (op:x:y:z:_) state i input output 
   | last (digits op) == 1 = do
-	   let newindex = index + 4
+	   let newindex = i + 4
            let newstate = add (fillup (revertdigs op) 5) x y z state
 	   operation (drop newindex newstate) newstate newindex input output
   | last (digits op) == 2 = do 
-           let newindex = index + 4
+           let newindex = i + 4
            let newstate = mult (fillup (revertdigs op) 5) x y z state
-           Amplifier state newindex input output  
-	   --operation (drop newindex newstate) newstate newindex input output
+	   operation (drop newindex newstate) newstate newindex input output
   | last (digits op) == 3 = do
-	   let newindex = index + 2
-           let newstate = put (fillup (revertdigs op) 3) x (head input) state
-           let newinput = drop 1 input  
-           operation (drop newindex newstate) newstate newindex newinput output
+	   if length input == 0
+              then Amplifier state i input output  
+              else do
+	        let newindex = i + 2
+                let newstate = put (fillup (revertdigs op) 3) x (head input) state
+                let newinput = drop 1 input  
+                operation (drop newindex newstate) newstate newindex newinput output
   | last (digits op) == 4 = do
-	   let newindex = index + 2
+	   let newindex = i + 2
 	   let newoutput = out (fillup (revertdigs op) 3) output x state
 	   let newinput = drop 1 input
            operation (drop newindex state) state newindex input newoutput
   | (last (digits op) == 5 )  = do
-	   let newindex = jumpif (fillup (revertdigs op) 4) x y index state
+	   let newindex = jumpif (fillup (revertdigs op) 4) x y i state
            operation (drop newindex state) state newindex input output
   | (last (digits op) == 6 )  = do
-	   let newindex = jumpifnot (fillup (revertdigs op) 4) x y index state
+	   let newindex = jumpifnot (fillup (revertdigs op) 4) x y i state
            operation (drop newindex state) state newindex input output
   | (last (digits op) == 7 ) = do
-	  let newindex = index + 4
+	  let newindex = i + 4
           let newstate = lessthan (fillup (revertdigs op) 5) x y z state
           operation (drop newindex newstate) newstate newindex input output  
   | (last (digits op) == 8 ) = do
-	  let newindex = index + 4
+	  let newindex = i + 4
           let newstate = equal (fillup (revertdigs op) 5) x y z state
           operation (drop newindex newstate) newstate newindex input output