2010002110

There is a part of the function $$f(x)=\{\begin{array}{ccc}& (x+6{)}^{-2}+2& x\in (-\mathrm{\infty };-5)\setminus \{-6\}\\ & 3,& x\in [-5;-3]\\ & 1,& x\in (-3;-1)\\ & |x-1|-1& x\in [-1,\mathrm{\infty })\setminus \{6\}\end{array}$$ in the picture. Use the graph to determine at how many points of the given interval $[-8;7]$ is the function $f$ defined and is not differentiable.