Add thanos sort

ThanosSort.nim

@@ -0,0 +1,20 @@
+proc thanosSort(list:seq[int]): seq[int] = 
+    proc isSorted(list:seq[int]):bool =
+        for i in list.low .. list.high - 1:
+            if list[i] > list[i+1]:
+                return false
+        return true
+
+    proc snap(list:seq[int]):seq[int] =
+        for i in list.low .. (list.high div 2):
+            result.add list[i * 2]
+
+    result = list
+
+    while not result.isSorted:
+        result = result.snap
+
+when isMainModule:
+    let
+        seq1 = @[1, 3, 5, 7, 23, 22, 13, 74, 4223, 3, 665, 62, 245, 2, 57, 3, 2, 4, 7, 4]
+    echo seq1.thanosSort