Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

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

Ali Dahud
Ali Dahud
3,459 Points

can you explain please?

On lines 12,17,22,27 why did we increment/decrement the values?

movement.py
# EXAMPLES:
# 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):
        x -= 1
        if x < 0:
            hp -= 5
            x += 1
    elif direction == (1,0):
        x += 1
        if x > 9:
            hp -= 5
            x -= 1
    elif direction == (0,-1):
        y -= 1
        if y < 0:
            hp -= 5
            y += 1
    elif direction == (0,1):
        y += 1
        if y > 9:
            hp -= 5
            y -= 1
    return x, y, hp
Jake Kobs
Jake Kobs
9,215 Points

If you're speaking about the code where the x,y values are either -=1 or +=1, it's because if the player goes passed the specified location values ((0,0) to (9,9)), then he/she would be out of the specified area. For instance, doing y-=1 would move your player back to spot 9 on the y coordinate because you wouldn't want the player to be out of bounds.

1 Answer

Steven Parker
Steven Parker
231,248 Points

That's because the movement was already applied before testing to see if the boundary was crossed. If so, damage was applied to the "hp" value, and the additional increment or decrement puts the position back to where it was.