Data commit

Task/Sorting-algorithms-Merge-sort/CoffeeScript/sorting-algorithms-merge-sort.coffee

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+# This is a simple version of mergesort that returns brand-new arrays.
+# A more sophisticated version would do more in-place optimizations.
+merge_sort = (arr) ->
+  if arr.length <= 1
+    return (elem for elem in arr)
+  m = Math.floor(arr.length / 2)
+  arr1 = merge_sort(arr.slice 0, m)
+  arr2 = merge_sort(arr.slice m)
+  result = []
+  p1 = p2 = 0
+  while true
+    if p1 >= arr1.length
+      if p2 >= arr2.length
+        return result
+      result.push arr2[p2]
+      p2 += 1
+    else if p2 >= arr2.length or arr1[p1] < arr2[p2]
+      result.push arr1[p1]
+      p1 += 1
+    else
+      result.push arr2[p2]
+      p2 += 1
+
+do ->
+  console.log merge_sort [2,4,6,8,1,3,5,7,9,10,11,0,13,12]