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Python Python Collections (2016, retired 2019) Dungeon Game Hit points

Jordon Crichton
Jordon Crichton
1,868 Points

I am not sure what I am missing. The error says I am not hurting when hitting the wall.

Our move function takes this three-part tuple player and a direction tuple that's two parts, the x to move and the y (like (-1, 0) would move to the left but not up or down).

Finish the function so that if the player is being run into a wall, their hp is reduced by 5. Don't let them go past the wall. Consider the grid to be 0-9 in both directions. Don't worry about keeping their hp above 0 either.

# move((1, 1, 10), (-1, 0)) => (0, 1, 10)
# move((0, 1, 10), (-1, 0)) => (0, 1, 5)
# move((0, 9, 5), (0, 1)) => (0, 9, 0)

def move(player, direction):
    x, y, hp = player
    if direction == (-1,0):
    elif direction == (1,0):
    elif direction == (0,1):
    elif direction == (0,-1):
    elif direction == (-1,0) and x == 0:
        x = 0
        hp -= 5
    elif direction == ( 1,0) and x == 9:
        x = 9
        hp -= 5
    elif direction ==  (0,-1) and y == 0:
        hp -= 5
    elif direction == (0,1) and y == 9:
        hp -=5

    return x, y, hp

1 Answer

Steven Parker
Steven Parker
229,608 Points

Remember that an "if/elif" chain is efficient because it stops testing when any condition is met. And the first few tests look only at direction, so if they match, they will change a coordinate and not change the hp, even if a wall is being hit.

A few things to keep in mind while implementing this function:

  • don't assume the movement will be in only one direction
  • don't assume the motion will be only one step
  • check for wall collisions first
  • if a wall would be hit, change the hp but not the location