PHP bubble sorting and binary searching for instances

We learned the bubble sort and binary search sort algorithms in junior high school. I will introduce the examples of the bubble sort and binary search in PHP.

We learned the bubble sort and binary search sort algorithms in junior high school. next I will introduce the PHP bubble sort and binary query examples.

Bubble sort to give a random array

$ Arr = array (89,112,321,234 );

Statistics array:$ Num = count ($ arr );

Bubble sort in reverse order:

1. For ($ I = 0; $ I <$ num-1; $ I ++ ){
2. For ($ m = 0; $ m <$ num-1; $ m ++ ){
3. If ($ arr [$ m] <$ arr [$ m + 1]) {
4. $ Temp = $ arr [$ m];
5. $ Arr [$ m] = $ arr [$ m + 1];
6. $ Arr [$ m + 1] = $ temp;
7. }
8. // Echo $ arr [$ m].'
   ';
9. }
10. }
11. // Output the sorted result
12. Var_dump ($ arr );
13. // Bubble sequence
14. For ($ x = 0; $ x <$ num-1; $ x ++ ){
15. For ($ y = 0; $ y <$ num-1; $ y ++ ){
16. If ($ arr [$ y]> $ arr [$ y + 1]) {
17. $ Temp = $ arr [$ y];
18. $ Arr [$ y] = $ arr [$ y + 1];
19. $ Arr [$ y + 1] = $ temp;
20. }
21. }
22. }
23. // Output the sorted result
24. Var_dump ($ arr );
25. // Binary search
26. Function dichotomy ($ array, $ k, $ low = 0, $ high = 0 ){
27. If (count ($ array )! = 0 & $ high = 0 ){
28. $ High = count ($ array );
29. }
30. If ($ low <= $ high ){
31. $ Mid = intval ($ low + $ high)/2 );
32. If ($ array [$ mid] === k ){
33. Return $ mid;
34. } Elseif ($ k <$ array [$ mid]) {
35. Return dichotomy ($ array, $ k, $ low = 0, $ mid-1 );
36. } Else {
37. Return dichotomy ($ array, $ k, $ mid + 1, $ high );
38. }
39. } Else {
40. Return false;
41. }
42. }
43. // Output the search result
44. Echo dichotomy ($ arr, 23 );

Today, I briefly studied the most common sorting and binary lookup of the bubble method and wrote a simple case to enhance my learning of php, I also hope to provide some help to php learners in the future.