well if you follow PEMDAS (parenthesizes, exponents, multiplication, division, addition, subtraction) you would do 1 x 0 first so
1+1+1+1+1+1+1+1+1+1+1+1x0+1= ?
would go to
1+1+1+1+1+1+1+1+1+1+1+0+1= ?
then you would add them together getting the end result of
12