Answer
$\Rightarrow S_{1}=-1$
$\Rightarrow S_{2}=0$
$\Rightarrow S_{3}=-1$
$\Rightarrow S_{4}=0$
$\Rightarrow S_{5}=-1$
$\Rightarrow S_{6}=0$
Work Step by Step
$S_{1}=-1$
$\Rightarrow S_{2}=S_{1}+1=0$
$\Rightarrow S_{3}=S_{2}+\left( -1\right) =-1$
$\Rightarrow S_{4}=S_{3}+1=0$
$\Rightarrow S_{5}=S_{4}+\left( -1\right) =-1$
$\Rightarrow S_{6}=S_{5}+1=0$
