Added 2 problems to Leetcode: #34, #103

[mohitkhosla01]

#34 - Find First and Last Position of Element in Sorted Array

• https://leetcode.com/problems/find-first-and-last-position-of-element-in-sorted-array/
• 100%ile runtime complexity, 100%ile space complexity
• Asked in Amazon

#103 - Find First and Last Position of Element in Sorted Array

• https://leetcode.com/problems/binary-tree-zigzag-level-order-traversal/
• 98.77%ile runtime, 99.04%ile space complexity
• Asked in Amazon

[neerajjain92]

Awesome, it would be great if you can add a recursive version of this as well.
Something like this, Optimization in this is welcome

   static int left, right;
    public static int[] searchRange(int[] nums, int target) {
        left = -1;
        right = -1;
        searchRange(nums, 0,nums.length-1, target);
        int [] result = new int[]{left, right};
        return result;  
    }
    
    private static void searchRange(int []nums, int low, int high, int target) {
        if(low <= high) {
            
            int mid = low + (high - low) / 2;
            
            if(nums[mid] < target) {
                searchRange(nums, mid+1, high, target);
            } else if (nums[mid] > target) {
                searchRange(nums, low, mid-1, target);
            } else { // Data Match
                if(mid == 0 || (left == -1 && nums[mid-1] != target)) {
                    left = mid;
                }
                if(mid == nums.length - 1 || (right == -1 && nums[mid+1] != target)) {
                    right = mid;
                }
                
                if(left == -1) {
                    searchRange(nums, low, mid-1, target);
                } 
                if(right == -1) {
                    searchRange(nums, mid+1, high, target);
                }
            }
        }
    }