Data update

Task/Find-the-missing-permutation/FutureBasic/find-the-missing-permutation.basic

@@ -0,0 +1,31 @@
+void local fn Permute( string as CFStringRef, result as CFMutableArrayRef, current as CFStringRef )
+  if ( len(string) == 0 ) then MutableArrayAddObject( result, current ) : return
+  for NSUInteger i = 0 to len(string) - 1
+    unichar c = fn StringCharacterAtIndex( string, i )
+    CFMutableStringRef remainingStr = fn MutableStringWithString( string )
+    MutableStringDeleteCharacters( remainingStr, fn RangeMake( i, 1 ) )
+    CFStringRef newCurrent = fn StringByAppendingFormat( current, @"%C", c )
+    fn Permute( remainingStr, result, newCurrent )
+  next
+end fn
+
+local fn DoPermutations as CFStringRef
+  CFStringRef inputString = @"ABCD"
+  CFMutableArrayRef array1 = fn MutableArrayNew
+  fn Permute( inputString, array1, @"" )
+
+  CFArrayRef array2 = @[
+  @"ABCD", @"CABD", @"ACDB", @"DACB", @"BCDA", @"ACBD",
+  @"ADCB", @"CDAB", @"DABC", @"BCAD", @"CADB", @"CDBA",
+  @"CBAD", @"ABDC", @"ADBC", @"BDCA", @"DCBA", @"BACD",
+  @"BADC", @"BDAC", @"CBDA", @"DBCA", @"DCAB"]
+
+  CFMutableSetRef set1 = fn MutableSetWithArray( array1 )
+  CFSetRef set2 = fn SetWithArray( array2 )
+  MutableSetMinusSet( set1, set2 )
+  return fn SetAnyObject( set1 )
+end fn = NULL
+
+printf @"%@", fn DoPermutations
+
+HandleEvents