<p>You are given <code>row x col</code> <code>grid</code> representing a map where <code>grid[i][j] = 1</code> represents&nbsp;land and <code>grid[i][j] = 0</code> represents water.</p>

<p>Grid cells are connected <strong>horizontally/vertically</strong> (not diagonally). The <code>grid</code> is completely surrounded by water, and there is exactly one island (i.e., one or more connected land cells).</p>

<p>The island doesn&#39;t have &quot;lakes&quot;, meaning the water inside isn&#39;t connected to the water around the island. One cell is a square with side length 1. The grid is rectangular, width and height don&#39;t exceed 100. Determine the perimeter of the island.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img src="https://assets.leetcode.com/uploads/2018/10/12/island.png" style="width: 221px; height: 213px;" />
<pre>
<strong>Input:</strong> grid = [[0,1,0,0],[1,1,1,0],[0,1,0,0],[1,1,0,0]]
<strong>Output:</strong> 16
<strong>Explanation:</strong> The perimeter is the 16 yellow stripes in the image above.
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> grid = [[1]]
<strong>Output:</strong> 4
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> grid = [[1,0]]
<strong>Output:</strong> 4
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>row == grid.length</code></li>
	<li><code>col == grid[i].length</code></li>
	<li><code>1 &lt;= row, col &lt;= 100</code></li>
	<li><code>grid[i][j]</code> is <code>0</code> or <code>1</code>.</li>
	<li>There is exactly one island in <code>grid</code>.</li>
</ul>

from collections import deque
class Solution:
    def islandPerimeter(self, grid: List[List[int]]) -> int:
        self.m = len(grid)
        self.n = len(grid[0])
        self.q = deque()
        self.count = 0
        self.visited=set()
        self.land=set()
        self.neighbors = [(0,-1),(0,1),(1,0),(-1,0)]
        self.helper(grid)
        return self.count

    def helper(self,grid):

        self.q.append((0,0))
        while self.q:
            perimeter = 4
            i,j = self.q.popleft()
            self.visited.add((i,j))

            for x,y in self.neighbors:
                if 0<= i+x < self.m and 0<= j+ y <self.n:
                    if (i+ x,j+ y) not in self.visited and (i+ x,j+ y) not in self.q:
                        print((i+ x,j+ y))
                        self.q.append((i+ x,j+ y))
                    if grid[i+ x][j+ y] == 1 : # checking if the neighbor is land
                        perimeter -= 1
            if grid[i][j] == 1:
                if (i,j) not in self.land:
                    self.land.add((i,j))
                    self.count += perimeter
                    # if grid[i+ neighbor[0]][j+ neighbor[1]] == 1 and (i+ neighbor[0],j+ neighbor[1]) not in self.land:
                    #     self.land.add((i+ neighbor[0],j+ neighbor[1]))
        # iterate over land to get the perimeter:
        # for x, y in self.land:
        #     perimeter = 4
        #     for neighbor in self.neighbors:
        #         if (x+ neighbor[0],y+ neighbor[1]) in self.land:
        #             perimeter -= 1
        #     self.count += perimeter
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