-import "Prelude"\r
-\r
-data E = E String\r
-\r
-instance Additive E where\r
- zero = E "0"\r
- E a + E b = E ("(" + a + "+" + b + ")")\r
- \r
-instance Ring E where\r
- one = E "1"\r
- neg (E a) = E ("(-" + a + ")")\r
- E a - E b = E ("(" + a + "-" + b + ")")\r
- E a * E b = E ("(" + a + "*" + b + ")") \r
- fromInteger x = E (show x)\r
-\r
-eToString (E a) = a\r
-\r
-a = E "a"\r
-b = E "b"\r
-c = E "c"\r
-d = E "d"\r
-\r
-main = eToString (-a + b + (-c*d))\r
---\r
+import "Prelude"
+
+data E = E String
+
+instance Additive E where
+ zero = E "0"
+ E a + E b = E ("(" + a + "+" + b + ")")
+
+instance Ring E where
+ one = E "1"
+ neg (E a) = E ("(-" + a + ")")
+ E a - E b = E ("(" + a + "-" + b + ")")
+ E a * E b = E ("(" + a + "*" + b + ")")
+ fromInteger x = E (show x)
+
+eToString (E a) = a
+
+a = E "a"
+b = E "b"
+c = E "c"
+d = E "d"
+
+main = eToString (-a + b + (-c*d))
+--
(((-a)+b)+(-(c*d)))
\ No newline at end of file