hunry rabbit

Author: jordanpaulchan

hungry-rabbit/description.md

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+# Hungry rabbit
+
+There is a rabbit that starts in the middle of an n x m matrix, n > 0, m > 0.
+Each element of a matrix is an integer representing points gained for being on the spot.
+If there are multiple possible "middles" then choose the one which has the highest point value to start on.
+On each iteration, the rabbit can move up, left, right, or down.
+The rabbit will always move to the next spot with the highest point value and will "consume" those points (set the point value in that position to 0).
+The rabbit spots when all positions around it are 0s. Calculate how many points the rabbit will score for a given m x n matrix.
+
+## Example
+
+### Input
+
+5, 7, 8, 6, 3
+0, 0, 7, 0, 4
+4, 6, 3, 4, 9
+3, 1, 0, 5, 8
+
+### Output
+
+27
+
+## Run the program
+
+In the folder run the command:
+
+```
+python hungry-rabbit.py
+```

hungry-rabbit/hungry-rabbit.py

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+def hungry_rabbit_util(garden, row, col):
+ max = 0
+ next_row = None
+ next_col = None
+
+ for r, c in [[-1, 0], [1, 0], [0, -1], [0, 1]]:
+ if row + r >= 0 and row + r < len(garden) and \
+ col + c >= 0 and col + c < len(garden[row]):
+ if garden[row + r][col + c] > max:
+ max = garden[row + r][col + c]
+ next_row = row + r
+ next_col = col + c
+
+ carrots = garden[row][col]
+ garden[row][col] = 0
+
+ if max > 0 and next_row is not None and next_col is not None:
+ carrots += hungry_rabbit_util(garden, next_row, next_col)
+
+ return carrots
+
+
+def find_center(garden):
+ row_options = [len(garden) // 2, len(garden) // 2]
+ col_options = [len(garden[0]) // 2, len(garden[0]) // 2]
+
+ # If even, 1st option is one less than half the length
+ if len(garden) % 2 == 0:
+ row_options[0] -= 1
+
+ if len(garden[0]) % 2 == 0:
+ col_options[0] -= 1
+
+ max = 0
+ row = None
+ col = None
+
+ for r_option in row_options:
+ for c_option in col_options:
+ if garden[r_option][c_option] > max:
+ max = garden[r_option][c_option]
+ row = r_option
+ col = c_option
+
+ return row, col
+
+
+def hungry_rabbit(garden):
+ if len(garden) == 0 or len(garden[0]) == 0:
+ return 0
+
+ # create a copy of the garden so we can mutate it
+ copy = [g_row[:] for g_row in garden]
+ row, col = find_center(copy)
+
+ if row is None or col is None:
+ return 0
+
+ return hungry_rabbit_util(copy, row, col)
+
+
+if __name__ == "__main__":
+ garden = [
+ [5, 7, 8, 6, 3],
+ [0, 0, 7, 0, 4],
+ [4, 6, 3, 4, 9],
+ [3, 1, 0, 5, 8]
+ ]
+
+ print hungry_rabbit(garden)