Unrelated test

Author: odersky

tests/run/rainwater.check

@@ -0,0 +1 @@
+rainWater captured by List(0, 1, 0, 2, 1, 0, 1, 3, 2, 1, 2, 1) = 6

tests/run/rainwater.scala

@@ -0,0 +1,21 @@
+
+def rainWater(vec: List[Int]): Int =
+  if vec.isEmpty then 0
+  else
+    val mx = vec.max
+    val split = vec.indexWhere(_ == mx)
+      rainWater1(0, vec.take(split + 1))
+    + rainWater1(0, vec.drop(split).reverse)
+
+def rainWater1(mx: Int, xs: List[Int]): Int = xs match
+  case x :: rest =>
+    val newMx = x max mx
+    newMx - x + rainWater1(newMx, rest)
+  case _ =>
+    0
+
+def test(xs: Int*) =
+  println(s"rainWater captured by ${xs.toList} = ${rainWater(xs.toList)}")
+
+@main def Test =
+  test(0,1,0,2,1,0,1,3,2,1,2,1)