$3.(10$ points$)$ Implement the ternary heap structure $($each node can have up to $3$ children$).$ The heap must support the following methods:

$-$ Insert $()$

$-$ GetMin $()$

$-$ Heapify $($i$)/*$ swap the elements from i such that the array becomes a heap $*/$

$-$ DeleteMin $()$

$-$ BuildHeap $()/*$ rearrange the array to make it become a heap $*/$