$2.($Homework$)$ Consider the following algorithm.

$```$

A$\backslash$leftarrow$5$

for $\}$i$\backslash$leftarrow$1\backslash$mathrm$\{$ to $\}$n$\backslash$mathrm$\{$ do

for $\}$j$\backslash$leftarrow$1\backslash$mathrm$\{$ to $\}$i$\backslash$mathrm$\{$ do

for $\}$k$\backslash$leftarrowi$\backslash$mathrm$\{$ to $\}$n$\backslash$mathrm$\{$ do

$```$

$($a$)$ Find the efficiency of the algorithm.

$($b$)$ Write the value of $\backslash ($ A $\backslash )$ as a function of $\backslash ($ n $\backslash ).$