Priority Queue Removal Sum - Flipkart Online Assessment SDE Role IIIT Bhubaneswar - Flipkart Interview Question

You are given N elements to be inserted into a priority queue. Each element is represented as a pair (x, y), where:

x is the value of the element.
y is its priority.

A higher value of y indicates a higher priority.

If two elements have the same priority, the element inserted earlier is removed first (FIFO order for equal priorities).

Your task is to find the sum of the first K elements removed from the priority queue.

Input Format

The first line contains an integer N, the number of elements.
The next N lines each contain two integers:
- x — value of the element.
- y — priority of the element.
The last line contains an integer K, the number of elements to remove from the priority queue.

Output Format

Print a single integer representing the sum of the values of the first K elements removed from the priority queue.

Constraints

(x >= 0)
(y >= 0)

Sample Input 1

Sample Output 1

Explanation

The elements are removed in decreasing order of priority.

Insertion order:

(3,1)
(7,3)
(4,2)
(5,3)

Removal order:

(7,3)
(5,3)   // Same priority as 7, but inserted later, so removed after 7
(4,2)
(3,1)

The first K = 2 removed elements have values 7 and 5.

Sum = 7 + 5 = 12.