Q:

What is $2 - 1 + 1$?

$2-1+1$; a fairly straightforward question, but I (well, not me, but Henry Reich) found something strange.
Most people would evaluate it as $2+(-1)+1 = 2$; however, this goes against the famed, and fairly standard B.E.D.M.A.S./P.E.D.M.A.S., which states that addition goes first, and then subtraction.
If this is the case, then the answer is $2 - (1 + 1) = 2-2 =0$.
Which is the correct answer, and why is the conventional way (B.E.D.M.A.S./P.E.D.M.A.S.) so ambiguous?

A:

This is why those abbreviations are poor. PEMA is a better one for that purpose. 
By the way, normally it is PEMDAS (not PEDMAS) and it stands for Parenthesis, Exponentiation, Multiplication and Division, Addition and Subtract. It's just that the "and"s get lost in abbreviation. 

A:

According to standard algebra rules, $a - b$ parses as $a + (-b)$.

A:

Forget garbage like PEMDAS.  Learn mathematics instead.
(And I would take "AS" to mean "addition and subtraction", not "addition, then subtraction".  I learned in 6th and 7th grades that those are done from left to right.  If someone taught you a rule that addition should precede subtraction in such instances, they are ignorant.)

