java - insertion sort...tweaks to improve? -

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i know insertion sort isn't great...but still...what 2 more simple improvements made sort below?

public static void insertion_sort_with_moves(int[] arr){     (int = 1; <= arr.length; i++){         int v = arr[i-1];         int j = i-1;         (/*declared j outside loop*/; j > 0; j--) {             //compswap(a[j-1], a[j]);             if (v < arr[j-1]) arr[j] = arr[j-1];             else break;         }         arr[j] = v;     } }

a few micro-optimizations are:

1,2,3)

    int len = arr.length;  ...      (int = 0; < len; ++i){             int v = arr[i];             int j = i;

saves computing i-1 2 times , ++i faster i++. not sure length thing (could save offset addition when accessing class member).

4,5)

for (/*declared j outside loop*/; j != 0; --j) {

j!=0 should faster j>0 (really don't expect much) , --j faster j--.

well of them may platform dependent , may make no difference @ all.


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