# Kth largest element in an array

July 23, 2022

heapProblem URL: Kth largest element in an array

We can just sort the element and return second largest element from the array, but it will have `O(nlog(n))`

time complexity. But if we use a heap, then the time complexity will be `O(n)`

for heapify and then `O(log(n))`

for every element we pop from the heap.

```
class Solution:
def findKthLargest(self, nums: List[int], k: int) -> int:
nums = [-num for num in nums]
heapq.heapify(nums)
while k>0:
item = heapq.heappop(nums)
k -= 1
return -item
```

Time Complexity: `O(n+klog(n))`

, where n is the length of nums, and k is the value of k.

Space Complexity: `O(n)`