$4.$ Write a recursive equation for the running time T$($n$)$ of the function, whose code is below. Prove using the iterative method that T$($n$)=\backslash$theta $($n$3)$ function$($ int n $)\{$ if $($ n $==1)$ return ; for$($ i $=1$ ; i $<=$ n ; i $++)$ for$($ j $=1$ ; j $<=$ n ; j $++)$ print$(*")$ ; function$($ n$-3)$; $\}$