2010013805

Let $\mathrm{sgn}(x)=\{\begin{array}{ll}1,& x>0\\ 0,& x=0.\\ -1,& x<0\end{array}$ Evaluate the following definite integral. $$\underset{-2}{\overset{-1}{\int }}(\mathrm{sgn}(x-1)+1)\mathrm{d}x$$