'''

class Solution(object):

def islandPerimeter(self, grid):

"""

:type grid: List[List[int]]

:rtype: int

"""

i, j = 0, 0

sum = 0

if grid[0][0]:

sum += 4

```
for i in range(1,len(grid)):
if grid[i][0]:
if grid[i-1][0]:
sum += 2
else:
sum += 4
for j in range(1,len(grid[0])):
if grid[0][j]:
if grid[0][j-1]:
sum += 2
else:
sum += 4
for i in range(1,len(grid)):
for j in range(1, len(grid[0])):
if grid[i][j]:
if grid[i-1][j] and grid[i][j-1]:
# sum += 2-2 two sides inside of the intersection
pass
elif grid[i-1][j] or grid[i][j-1]:
# one side inside the intersection
sum += 2
else:
sum += 4
return sum
```

'''