Learning On the Way

1738. Find Kth Largest XOR Coordinate Value

You are given a 2D matrix of size m x n, consisting of non-negative integers. You are also given an integer k. The value of coordinate (a, b) of the matrix is the XOR of all matrix[i][j] where 0 <= i <= a < m and 0 <= j <= b < n (0-indexed). Find the kth largest value (1-indexed) of all the coordinates of matrix.

Matrix Block Sum

def kthLargestValue(self, matrix: List[List[int]], K: int) -> int: 
	R, C = len(matrix), len(matrix[0]) 
	arr = [] 
	for i in range(R): 
		for j in range(C): 
			if i and j: 
				matrix[i][j] ^= matrix[i-1][j]^matrix[i][j-1]^matrix[i-1][j-1] 
			elif i: 
				matrix[i][j] ^= matrix[i-1][j] 
			elif j: 
				matrix[i][j] ^= matrix[i][j-1] 
			arr.append(matrix[i][j]) 
	arr.sort() 
	return arr[-K]