54 lines
1.2 KiB
Python
54 lines
1.2 KiB
Python
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grid = [
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["1","1","1","1","0"],
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["1","1","0","1","0"],
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["1","1","0","0","0"],
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["0","0","0","1","0"]
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]
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def numIslands(grid):
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R = len(grid)
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C = len(grid[0])
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numIslands = 0
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def floodFill(grid, r,c):
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# Approach 1
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print(r,c,grid[r][c])
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if grid[r][c] == '1': # this means we can advance
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grid[r][c] = '0' # mark as visited
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if r>=1: floodFill(grid, r-1, c)
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if r+1<R: floodFill(grid, r+1, c)
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if c>=1: floodFill(grid, r, c-1)
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if c+1<C: floodFill(grid, r, c+1)
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# Approach 2 - check out of bounds
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if r < 0 or r >=R or c < 0 or c >= C or grid[r][c] == "0":
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return 0
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else:
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print(r,c,grid[r][c])
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grid[r][c] = '0' # mark as visited
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floodFill(grid, r-1, c)
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floodFill(grid, r+1, c)
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floodFill(grid, r, c-1)
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floodFill(grid, r, c+1)
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for i in range(R):
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for j in range(C):
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if grid[i][j]=='1':
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numIslands+=1
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floodFill(grid, i, j)
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print(grid)
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return numIslands
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print(numIslands(grid))
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