/**
 * ID:    00835
 * Title: Image Overlap
 * Difficulty: Medium
 * Description: You are given two images, img1 and img2, represented as binary, square matrices of size n x n. A binary matrix has only 0 s and 1 s 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:
 * 
 * Input: img1 = [[1,1,0],[0,1,0],[0,1,0]], img2 = [[0,0,0],[0,1,1],[0,0,1]] Output: 3 Explanation: We translate img1 to right by 1 unit and down by 1 unit. The number of positions that have a 1 in both images is 3 (shown in red).
 * 
 * Example 2:
 * 
 * Input: img1 = [[1]], img2 = [[1]] Output: 1
 * 
 * Example 3:
 * 
 * Input: img1 = [[0]], img2 = [[0]] Output: 0
 * 
 * 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.
 */
function solution() {
  
}

function test_00835() {
  
}

test_00835()
