Image Overlap
You are given two images, img1 and img2, represented as binary, square matrices of size n x n. A binary matrix has only 0s and 1s as values.
We translate one image however we choose by sliding all the 1 bits left, right, up, and/or down any number of units. We then place it on top of the other image. We can then calculate the overlap by counting the number of positions that have a 1 in both images.
Note also that a translation does not include any kind of rotation. Any 1 bits that are translated outside of the matrix borders are erased.
Return the largest possible overlap.
Example 1
1 1 0 0 1 0 0 1 0 0 0 0 0 1 1 0 0 1
Input
img1 = [[1,1,0],[0,1,0],[0,1,0]], img2 = [[0,0,0],[0,1,1],[0,0,1]]Output
3We translate img1 to right by 1 unit and down by 1 unit, giving 3 positions that have a 1 in both images.
Example 2
1 1
Input
img1 = [[1]], img2 = [[1]]Output
1Both images contain a single 1 in the same position, so the maximum overlap is 1.
Constraints
- n == img1.length == img1[i].length
- n == img2.length == img2[i].length
- 1 <= n <= 30
- img1[i][j] is either 0 or 1.
- img2[i][j] is either 0 or 1.
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