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

Sahar Nasiri
Sahar Nasiri
7,454 Points

It is not working!

What is wrong with my code that makes it not work?

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 x == 0 & (direction[0] < 0):
        x, y, hp = x, direction[1] + y, hp - 5
    if x == 9 & (direction[0] > 0):
        x, y, hp = x, direction[1] + y, hp - 5
    if y == 0 & (direction[1] < 0):
        x, y, hp = direction[0] + x, y, hp - 5 
    if y == 9 & (direction[1] > 0):
        x, y, hp = direction[0] + x, y, hp - 5 
    else:
        x, y, hp = direction[0] + x, direction[1] + y, hp

    return x, y, hp

2 Answers

The ampersand (&) is the so-called "bitwise" AND operator in Python, it can only be used on integer values by default, and works differently than the conditional AND (what we usually need), for which the keyword is and.

Christian Mangeng
Christian Mangeng
15,970 Points

Hi Sahar,

Gyorgy is right, you need to use "and" instead of "&". Also, why do you want to change the position of the player if the player performs an invalid move? The only thing that should happen in that case is that hp is reduced by 5.

One useful advice here: it is a good idea to unpack the direction variable in this case for reasons of readability (you assign direction[0] to "a" and direction[1] to "b"):

a, b = direction

Good luck

Sahar Nasiri
Sahar Nasiri
7,454 Points

Thanks for your great advice :)