835. Image Overlap

https://leetcode.com/problems/image-overlap/
Python

class Solution:
    def largestOverlap(self, img1: List[List[int]], img2: List[List[int]]) -> int:
        n = len(img1)

        def count_overlay(start_row, start_col):
            up_left, up_right, down_left, down_right = 0, 0, 0, 0

            for row_ref, row_move in enumerate(range(start_row, n)):
                for col_ref, col_move in enumerate(range(start_col, n)):
                    if img1[row_move][col_move] and img2[row_ref][col_ref]:
                        up_left += 1

                    if img1[row_move][col_ref] and img2[row_ref][col_move]:
                        up_right += 1

                    if img1[row_ref][col_ref] and img2[row_move][col_move]:
                        down_left += 1

                    if img1[row_ref][col_move] and img2[row_move][col_ref]:
                        down_right += 1

            return max(up_left, up_right, down_left, down_right)

        ans = 0
        for r in range(n):
            for c in range(n):
                ans = max(ans, count_overlay(r, c))
        return ans
Python​

Python
