Data update

Task/Quickselect-algorithm/YAMLScript/quickselect-algorithm.ys

@@ -0,0 +1,25 @@
+!YS-v0
+
+v =: +[9 8 7 6 5 0 1 2 3 4]
+
+defn main():
+  say:
+    map \(quickselect v _):
+      v.#:range
+
+defn quickselect(a k):
+  loop arr a:V, current-k k:
+    pivot-idx =: arr.#:rand-int
+    pivot =: arr.$pivot-idx
+    remaining =:
+      concat subvec(arr 0 pivot-idx):
+             subvec(arr pivot-idx.++)
+    left =: remaining.filter(\(_ < pivot))
+    right =: remaining.filter(\(_ >= pivot))
+    left-count =: left.#
+    cond:
+      current-k == left-count: pivot
+      current-k < left-count:
+        recur: left:V current-k
+      else:
+        recur right:V: (current-k - left-count).--