package leetcode func islandPerimeter(grid [][]int) int { counter := 0 for i := 0; i < len(grid); i++ { for j := 0; j < len(grid[0]); j++ { if grid[i][j] == 1 { if i-1 < 0 || grid[i-1][j] == 0 { counter++ } if i+1 >= len(grid) || grid[i+1][j] == 0 { counter++ } if j-1 < 0 || grid[i][j-1] == 0 { counter++ } if j+1 >= len(grid[0]) || grid[i][j+1] == 0 { counter++ } } } } return counter }