Why am I getting a StackOverFlow Error?

[whoareyou]

Can somebody please tell me why I'm getting a stack over flow error when I try to apply the merge sort in my main program?

code:

//Recursive mergesort     //This method recrursively sorts the section of the array from start to "end", Inclusive     public void Merge_Sort (int[] array, int start, int end)     {         //Calculate the length of this range of the array         int length = end - start + 1;         //If the length is 1, there's no work to do         //So return 0         if (length <= 0)         {             return;         }         //If the length is 2, check to see if the values are out of order, and if so, swap them.         //Return 1         if (length == 2)         {             if (array [start] > array [end])             {                 int temp = array [start];                 array [start] = array [end];                 array [end] = temp;                 return;             }             return;         }         //Find the middle of the range         int mid = (start + end) / 2;         //Mergesort the left half         Merge_Sort (array, start, mid);         //Mergesort the right half         Merge_Sort (array, mid + 1, end);         //Copy the left half of the range into a new array         int[] left = new int [mid - start + 1];         //Copy the right half of the range into a new array         int[] right = new int [end - mid + 1];         //Merge the left and right halves         Merge (left, right);         //Copy the results of the merge back into the main array         for (int i = 0 ; i < temp.length ; i++)         {             array [i] = temp [i];         }         //Return a value indicating how much work was done.     }     //This method merges two arrays of integers, and returns the result in a new array     //We are assuming that the two lists are each already sorted     protected void Merge (int[] left, int[] right)     {         //Create a new array to store the results (must be big enough to hold all the values left and right)         temp = new int [left.length + right.length];         //Create a variable to track where we are in each array (leftIndex and rightIndex)         int leftIndex = 0;         int rightIndex = 0;         //Loop from the start of out result array to the end         for (int i = 0 ; i < temp.length ; i++)             {                 //If leftIndex is more than the length of the "left" array, copy the value of "right" array into the result array, and increase rightIndex by 1                 if (leftIndex >= left.length)                 {                     temp [i] = right [rightIndex];                     rightIndex++;                 }                 //Else if the rightIndex is more than the length of the "right" array, copy the value of the "left" array into the result array, and increase leftIndex by 1                 else if (rightIndex >= right.length)                 {                     temp [i] = left [leftIndex];                     leftIndex++;                 }                 //Else if  the value in the "left" array is less than the value in the "right" array, copy the value in the "left" array into the result array, increase leftIndex by 1                 else if (left [leftIndex] < right [rightIndex])                 {                     temp [i] = left [leftIndex];                     leftIndex++;                 }                 //Else copy the value in the "right" array into the result array, and increase rightIndex by 1                 else                 {                     temp [i] = right [rightIndex];                     rightIndex++;                 }                 //End if                 //End loop             }     }

[Zren]

Read your first 10 lines carefully. What happens if start and end are the same number? Or in other words, a subsection of length 1.

A good technique for debugging recursion would be to log each time a recursive function is called and what the parameters were. Here's a helpful code snippet for you.

Java:

System.out.format("MergeSort(%s, %d, %d)%n", Arrays.toString(array), start, end);