$5.$ Write a recurrence relation describing the worst case running time of the following algorithmand determine the asymptotic complexity of the function defined by the recurrence relation.Justify your solution using substitution$/$expansion or a recursion tree. You may not use theMaster Theorem as justification of your answer. Simplify and express your answer as $($nk$)$or $($nk log$2$ n$)$ whenever possible. If the algorithm is exponential just give exponentiallower bounds.function func$($A$,$n$)$ if n $<=5$ then return A$(1)$ elsefor i $=1$ to nfor j $=$ i to n$-1$ A$($j$)$ A$($j$)+$ A$($i$)+3/*$ endfor $*//*$ endfor $*/$y func$($A$,$ n$-6)$ return $($y$)2$