,\\ q_{0}(t)=-\frac{0}{0}t+0sgn(t)\left(e^{- \mid t\mid}-0\right),\\ q_{0}(t)=-\frac{0}{0}t+0sgn(t)\left(e^{- \mid t\mid}-0\right). \end{array}\right. \label{case0}\end{aligned}$$ The associated two-peakon solution of (\[eq\]) becomes $$\begin{aligned} u(x,t)=v(x,t)=e^{-\left|x+\frac{0}{0}t-0sgn(t)\left(e^{- \mid t\mid}-0\right)\right|}+0e^{-\left|x+\frac{0}{0}t-0sgn(t)\left(e^{- \mid t\mid}-0\right)\right|}