# Kth Largest Numbers From Stream - Amazon Top Interview Questions

### Problem Statement :

```Implement a data structure with the following methods:

KthLargestStream(int[] nums, int k) which constructs the instance.
int add(int val) which adds val to nums and returns the k (0-indexed) largest value in nums
Constraints

1 ≤ n ≤ 100,000 where n is the length of nums
0 ≤ m ≤ 100,000 where m is the number of calls to add
k + 1 ≤ n

Example 1

Input

arguments = [[[1, 2, 4, 3], 3], , , , ]`

Output

[None, 2, 3, 4, 5]

Explanation

s = KthLargestStream([1,2,4,3],3)

s.add(5) == 2 # Stream has [1, 2, 3, 4, 5]

s.add(6) == 3 # Stream has [1, 2, 3, 4, 5, 6]

s.add(7) == 4 # Stream has [1, 2, 3, 4, 5, 6, 7]

s.add(8) == 5 # Stream has [1, 2, 3, 4, 5, 6, 7, 8]```

### Solution :

```                        ```Solution in C++ :

class KthLargestStream {
public:
KthLargestStream(vector<int>& nums, int k) {
K = k + 1;
for (auto& num : nums) {
pq.push(num);
if (pq.size() > K) {
pq.pop();
}
}
}

pq.push(val);
if (pq.size() > K) {
pq.pop();
}

return pq.top();
}

private:
priority_queue<int, vector<int>, greater<int>> pq;
int K;
};```
```

```                        ```Solution in Java :

import java.util.*;

class KthLargestStream {
PriorityQueue<Integer> pq;
int k;
public KthLargestStream(int[] nums, int k) {
this.pq = new PriorityQueue<Integer>();
this.k = k;
for (int num : nums) {
if (pq.size() > k + 1)
pq.poll();
}
}

if (pq.size() > k + 1)
pq.poll();
return pq.peek();
}
}```
```

```                        ```Solution in Python :

class KthLargestStream:
def __init__(self, nums, k):
heapq.heapify(nums)

while len(nums) > k + 1:
heapq.heappop(nums)

self.nums = nums

heapq.heappushpop(self.nums, val)

return self.nums```
```

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## Reverse a doubly linked list

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## Tree: Preorder Traversal

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## Tree: Postorder Traversal

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## Tree: Inorder Traversal

In this challenge, you are required to implement inorder traversal of a tree. Complete the inorder function in your editor below, which has 1 parameter: a pointer to the root of a binary tree. It must print the values in the tree's inorder traversal as a single line of space-separated values. Input Format Our hidden tester code passes the root node of a binary tree to your \$inOrder* func

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