5. The graph of $y=-1-2^{x}$ is reflected about the line $y=x$ to obtain graph $c_{1}$, the graph $c_{1}$ is reflected about the origin to obtain $c_{2}$, and the graph $c_{2}$ is translated one unit to the left along the $x$-axis to obtain $c_{3}$. Then, the function corresponding to $c_{3}$ is $\qquad$
\begin{array}{l}\text { 5. } y=\log _{\frac{1}{2}} x . \\ y=-1-2^{x} \rightarrow y=\log _{2}(-1-x) \rightarrow -y=\log _{2}(-1+x) \rightarrow y=\log _{2} x \text {, i.e., } y=-\log _{2} x \text {. }\end{array}