Can someone help me with this in C$++$

I need help implementing the functions below. The attached photos are the $.$h files that are the declations for the other $.$h files below:

Below is heap.h

#ifndef HEAP$\_$H

#define HEAP$\_$H

#include

#include

inline constexpr size$\_$t heap$\_$left$($size$\_$t node$)\{$

$//$ XXX You must implement this.

return $999$;

$\}$

inline constexpr size$\_$t heap$\_$right$($size$\_$t node$)\{$

$//$ XXX You must implement this.

return $999$;

$\}$

inline constexpr size$\_$t heap$\_$parent$($size$\_$t node$)\{$

$//$ XXX You must implement this.

return $999$;

$\}$

template

void heap$\_$preorder$($ArrayLike heapdata, size$\_$t heapnodes, size$\_$t node, FN fn$)\{$

$//$ XXX You must implement this.

$\}$

template

void heap$\_$inorder$($ArrayLike heapdata, size$\_$t heapnodes, size$\_$t node, FN fn$)\{$

$//$ XXX You must implement this.

$\}$

template

void heap$\_$postorder$($ArrayLike heapdata, size$\_$t heapnodes, size$\_$t node, FN fn$)\{$

$//$ XXX You must implement this.

$\}$

template

void heap$\_$levelorder$($ArrayLike& heapdata, size$\_$t heapnodes, FN fn$)\{$

$//$ XXX You must implement this.

$\}$

$//$ min tree uses less than, so compare$($parent$,$ child$)$ should be true

template

bool is$\_$heap$($const ArrayLike& heapdata, size$\_$t nodes, COMPARISON compare$)\{$

$//$ XXX You must implement this properly.

return false;

$\}$

template

size$\_$t heap$\_$bubble$\_$up$($RAIterator begin, size$\_$t nodes, size$\_$t start, COMPARE compare$)\{$

$//$ XXX You must implement this properly.

return $9999999$;

$\}$

template

size$\_$t heap$\_$bubble$\_$down$($RAIterator begin, size$\_$t nodes, size$\_$t start, COMPARE compare$)\{$

$//$ XXX You must implement this properly.

return $9999999$;

$\}$

template

void heap$\_$insert$($CONTAINER& heapdata, size$\_$t& nodes, T key, COMPARISON compare$)\{$

$//$ XXX You must implement this properly.

$\}$

template

auto heap$\_$extract$($CONTAINER& heapdata, size$\_$t& nodes, COMPARISON compare$)\{$

$//$ XXX You must implement this properly.

return heapdata$[9999999]$;

$\}$

template

size$\_$t heapify$\_$in$\_$place$\_$up$($RAIterator begin, RAIterator end, COMPARE compare$)\{$

$//$ XXX You must implement this properly.

return $9999999$;

$\}$

template

size$\_$t heapify$\_$in$\_$place$\_$down$($RAIterator begin, RAIterator end, COMPARE compare$)\{$

$//$ XXX You must implement this properly.

return $9999999$;

$\}$

template

void heap$\_$sort$($RAIterator begin, RAIterator end, COMPARE compare$)\{$

$//$ XXX You must implement this properly.

$\}$

#endif

Below is heap$\_$priority$\_$queue.h

#ifndef HEAP$\_$PQ$\_$H

#define HEAP$\_$PQ$\_$H

#include "heap$\_$priority$\_$queue.decl.h$"$

template

template

heap$\_$priority$\_$queue::heap$\_$priority$\_$queue$($ITERATOR begin, ITERATOR end$)\{$

$//$ XXX this must be implemented properly.

$\}$

template

T& heap$\_$priority$\_$queue::top$()\{$

$//$ XXX this must be implemented properly.

static T x; return x; $//$ intentionally wrong, but will compile

$\}$

template

bool heap$\_$priority$\_$queue::empty$()$ const $\{$

$//$ XXX this must be implemented properly.

return true;

$\}$

template

size$\_$t heap$\_$priority$\_$queue::size$()$ const $\{$

$//$ XXX this must be implemented properly.

return $999999$; $//$ intentionally wrong

$\}$

template

void heap$\_$priority$\_$queue::push$($const T& x$)\{$

$//$ XXX this must be implemented properly.

$\}$

template

void heap$\_$priority$\_$queue::pop$()\{$

$//$ XXX this must be implemented properly.

$\}$

$//$ This one is provided for you and does not need changes.

template

void heap$\_$priority$\_$queue::dump$\_$data$($std::ostream& ost$)$ const $\{$

ost ;

for $($size$\_$t i $=0$; i $$ nodes; $++$i$)\{$

ost $$ data$[$i;

$\}$

ost ;

$\}$

#endif