Island Perimeter

Given a grid of 0s and 1s, where 1 represents land and 0 represents water, calculate the perimeter of all the islands in the grid. The perimeter of an island is the total number of edges that touch water or the grid's boundary. The input ends with a line containing '0'. Return the total perimeter of all islands in the grid. Example Input: 1 1 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 Example Output: 8