Add 'game-sml/' from commit '113c3e67abe635f714f972a1e2ab0e4b24ff10f4'

git-subtree-dir: game-sml
git-subtree-mainline: aa5357714d
git-subtree-split: 113c3e67ab

game-sml/fcore/bin-search.sml

@@ -0,0 +1,34 @@
+structure BinSearch =
+struct
+  fun helpExists (findNum, vec, low, high) =
+    if high >= low then
+      let
+        val mid = low + ((high - low) div 2)
+        val curNum = Vector.sub (vec, mid)
+      in
+        if curNum = findNum then true
+        else if curNum < findNum then helpExists (findNum, vec, mid + 1, high)
+        else helpExists (findNum, vec, low, mid - 1)
+      end
+    else
+      false
+
+  fun exists (findNum, vec) =
+    helpExists (findNum, vec, 0, Vector.length vec - 1)
+
+  fun helpFind (findNum, vec, low, high) =
+    if high >= low then
+      let
+        val mid = low + ((high - low) div 2)
+        val curNum = Vector.sub (vec, mid)
+      in
+        if curNum = findNum then mid
+        else if curNum < findNum then helpFind (findNum, vec, mid + 1, high)
+        else helpFind (findNum, vec, low, mid - 1)
+      end
+    else
+      ~1
+
+  fun find (findNum, vec) =
+    helpFind (findNum, vec, 0, Vector.length vec - 1)
+end