ou will now extend the functionality of the map library we are constructing. Add the functions to

the appropriate C file as the naming above would indicate.

i$.(10$ points$)$ Write a function called map add ordered key that takes $4$ arguments:

$(1)$ a pointer to struct map list,

$(2)$ a key to add, and

$(3)$ the value corresponding to the added key.

$(4)$ a function pointer with the signature int cmp key$($char $*$item key, char $*$add key$)$

As with the normal add function, this function should find a node on the free$-$list and add it

to the list. However, this function should repeatedly call the cmp key function provided with

the key to add and the current list item$$s key. The cmp key function should match the API of

strncmp $($returning $-1,0,$ and $1$ respectively$).$ The map add ordered key function should find

locate the first equal item $($or the end of the list$),$ and insert the new node. As with regular

add, this function should return $0$ if the item is added successfully, and $-1$ if not