class Solution {
public int[] searchRange(int[] nums, int target)
{
int first = firstIndex(nums, 0, nums.length, target);
int last = lastIndex(nums, 0, nums.length, target);
return new int[] {first, last};
}
public int firstIndex (int[] nums, int left, int right, int target)
{
while (left <= right)
{
int pivot = left + (right - left) / 2;
if (nums[pivot] == target)
{
if (pivot == left || nums[pivot - 1] < nums[pivot])
// it means the search on left side is done or mid is the first occurance in the array
return pivot;
else
// still go left
right = pivot - 1;
}
else if (nums[pivot] > target)
right = pivot - 1;
else
left = pivot + 1;
}
return -1;
}
public int lastIndex (int[] nums, int left, int right, int target)
{
while (left <= right)
{
int pivot = left + (right - left) / 2;
if (nums[pivot] == target)
{
if (pivot == right || nums[pivot] < nums[pivot + 1])
// it means the search on the right side is done or mid is the last occurance in the array
return pivot;
else
// still go right
left = pivot + 1;
}
else if (nums[pivot] > target)
right = pivot - 1;
else
left = pivot + 1;
}
return -1;
}
}
Here is my solution using binary search. It can be accepted when I run the code but cannot be submitted. There is an ArrayIndexOutOfBoundsException at if (nums[pivot] == target). I couldn't understand why this happened. And I looked into solutions. Most of the solution using this way. I don't know how to get rid of this error. Can somebody help me explain this???? Thank you so much!!!!
