LeetCode/LeetCode_34.java at main · Sujoy-mondal14/LeetCode · GitHub

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class Solution {
    public int[] searchRange(int[] nums, int target) {
        int[] ans = {-1,-1};

        //firstOccurence->
        ans[0] = search(nums,target, true);// finding firstIdx = true
        if(ans[0] != -1)  // lastOccurence->
        ans[1] = search(nums,target, false); // finding firstIdx = false;

        return ans;
    }

    int search(int[] nums, int target, boolean isFirstIdx){
        int ans = -1;
        int start = 0;
        int end = nums.length-1;

        while(start<=end){
            int mid = start + (end- start)/2;

            if(target > nums[mid]) start = mid +1;
            else if(target < nums[mid]) end = mid -1;
            else {
                ans = mid;

                if(isFirstIdx){
                    end = mid -1;
                }
                else{
                    start = mid+1;
                }
            }
        }

        return ans;
    }
}