Let g(x) = f(x) + f(2+x), where
\( f\left( x \right) = \left\{ {\begin{array}{*{20}{c}} {1 - \left| x \right|,\;\;\left| x \right| \le 1}\\ {0,\;\;\left| x \right| > 1} \end{array}} \right.\)
The number of points where the function g is not differentiable is
1
4
2
5
3
6
4
7