Xcode gives 3 syntax errors related to Stray '\ 342' in the program

Question

I am working on a simple project in Objective-C in Xcode, and I am getting some errors / errors in the following line of code:

if(celsius < −273.15) { NSLog(@"It is impossible to convert temperatures less than −273.15 degrees Celsius, because this is absolute zero, the coldest possible temperature."); } 

This is actually only the first line, but I would like to give some context.

Any suggestions?

I looked at it here on SO, but all the other errors did not have as simple code as mine, although they seem to have a common problem with the wrong encoding for a certain punctuation, maybe?

It must be some kind of syntax for this in my if statement.

UPDATE:

It appears that it also displays two other errors:

Stray '\ 210' Stray '\ 222'

Answer 1

-! = -

Your minus is not a minus.

Answer 2

Make sure your “characters” are straight up and down (and not left / right).