1+ /*
2+ Wikipedia says: Cycle sort is an in-place, unstable sorting algorithm,
3+ a comparison sort that is theoretically optimal in terms of the total
4+ number of writes to the original array, unlike any other in-place sorting
5+ algorithm. It is based on the idea that the permutation to be sorted can
6+ be factored into cycles, which can individually be rotated to give a sorted result.
7+ */
8+ function cycleSort ( list ) {
9+ 10+ let writes = 0 ;
11+ for ( let cycleStart = 0 ; cycleStart < list . length ; cycleStart ++ ) {
12+ 13+ let value = list [ cycleStart ] ;
14+ let position = cycleStart ;
15+ 16+ // search position
17+ for ( let i = cycleStart + 1 ; i < list . length ; i ++ ) {
18+ 19+ if ( list [ i ] < value ) {
20+ position ++ ;
21+ }
22+ }
23+ // if its the same continue
24+ if ( position == cycleStart ) {
25+ continue ;
26+ }
27+ 28+ while ( value == list [ position ] ) {
29+ position ++ ;
30+ }
31+ 32+ let oldValue = list [ position ] ;
33+ list [ position ] = value ;
34+ value = oldValue ;
35+ writes ++ ;
36+ 37+ // rotate the rest
38+ while ( position != cycleStart ) {
39+ position = cycleStart ;
40+ for ( let i = cycleStart + 1 ; i < list . length ; i ++ ) {
41+ 42+ if ( list [ i ] < value ) {
43+ position ++ ;
44+ }
45+ }
46+ while ( value == list [ position ] ) {
47+ position ++ ;
48+ }
49+ let oldValueCycle = list [ position ] ;
50+ list [ position ] = value ;
51+ value = oldValueCycle ;
52+ writes ++ ;
53+ }
54+ }
55+ return writes ;
56+ }
57+ let arrOrignal = [ 5 , 6 , 7 , 8 , 1 , 2 , 12 , 14 ] ;
58+ //Array before Sort
59+ console . log ( arrOrignal ) ;
60+ cycleSort ( arrOrignal ) ;
61+ //Array after sort
62+ console . log ( arrOrignal ) ;
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