1.

Given a sorted doubly linked list of positive distinct elements, the task is to find pairs in a doubly-linked list whose sum is equal to given value x, without using any extra space

Example:  

Input : head : 1 <-> 2 <-> 4 <-> 5 <-> 6 <-> 8 <-> 9
        x = 7
Output: (6, 1), (5,2)

The expected time complexity is O(n) and auxiliary space is O(1).

2.

Given an array nums of n elements and q queries . Each query consists of two integers l and r . You task is to find the number of elements of nums[] in range [l,r] which occur atleast k times.
 

Example 1:

Input: nums = {1,1,2,1,3}, Queries = {{1,5},
{2,4}}, k = 1
Output: {3,2}
Explanation: For the 1st query, from l=1 to r=5
1, 2 and 3 have the frequency atleast 1.
For the second query, from l=2 to r=4, 1 and 2 have
the frequency atleast 1.

 

Your Task:

Your task is to complete the function solveQueries() which takes nums, Queries and k as input parameter and returns a list containg the answer for each query.
 

Expected Time Complexity: O(n*sqrt(n)*log(n))
Expected Space Compelxity: O(n)
 

Constraints:
1 <= n, no of Queries, k <= 104
1 <= nums[i] <= 103

1 <= Queries[i][0] <= Queries[i][1] <= n

3.

Given an array of integers. Write a program to find the K-th largest sum of contiguous subarray within the array of numbers which has negative and positive numbers.

Examples: 

Input: a[] = {20, -5, -1}
         k = 3
Output: 14
Explanation: All sum of contiguous
subarrays are (20, 15, 14, -5, -6, -1)
so the 3rd largest sum is 14.
Input: a[] = {10, -10, 20, -40}
         k = 6
Output: -10
Explanation: The 6th largest sum among
sum of all contiguous subarrays is -10.