Multiple boolean operators

Question

could someone please explain to me why this code returns True? I totally don't understand this one, for my understanding, it should return False.

z = 2
y = 1
x = y < z or z > y and y > z or z < y
print(x)

also this example makes little sense in real life as `y < z or z > y` boils down to `y < z` — Jean-François Fabre, Jun 26 '19 at 20:37

score 0 · Accepted Answer · answered Jun 26 '19 at 20:33

and binds more (based on operator precendence) than or does. Hence, your boolean expression could also be represented like this:

z = 2
y = 1
x = y < z or (z > y and y > z) or z < y
print(x)

Clearly, y < z is True and because only one of the three needs to be True, the whole expression evaluates to True.

score 0 · Answer 2 · answered Jun 26 '19 at 20:33

0

or has a lower operator precedence than and, so y < z or z > y and y > z or z < y is equivalent to (y < z) or (z > y and y > z) or (z < y), and since y < z is True, the entire expression is therefore True after the evaluation of the or operations.

answered Jun 26 '19 at 20:33

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Multiple boolean operators

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