java - Why does my binary search produce an ArrayIndexOutOfBoundsException? -

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i using eclipse. code: 

private int binarysearch(int[] arraysorted, int value, int min, int max) {     if (max < min) {         return -1;     } else {         int mid = min + max / 2;         if (value > arraysorted[mid]) // line 22             return binarysearch(arraysorted, value, mid + 1, max);         else if (value < arraysorted[mid])             return binarysearch(arraysorted, value, min, mid - 1);         else             return mid;     } }

and error:

exception in thread "main" java.lang.arrayindexoutofboundsexception: 7 @ launcher.binarysearch(launcher.java:22) @ launcher.binarysearch(launcher.java:23) @ launcher.main(launcher.java:14)

i call method so: 

int[] arraysorted = { 0, 1, 2, 2, 4, 7, 99 }; binarysearch(arraysorted, searchnum, 0, arraysorted.length - 1);

can figure out why getting this? how can identify issue using debugger?

the middle index element calculated incorrectly because of missing parentheses.

it should be:

int mid = (min + max) / 2;

and not 

int mid = min + max / 2;

which calculates, adding unnecessary parentheses, min + (max / 2).

you can find out problem doing step-by-step analysis of code favorite debugger.


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