69,371
社区成员
发帖
与我相关
我的任务
分享
void AI_PushPriorityQueue( queue_t &pqueue, node_t *node)
{
pqueue.heap.push_back( node );
std::push_heap( pqueue.heap.begin(), pqueue.heap.end(), AI_NodeTotalGreater() );
}
struct queue_t
{
//std::vector<node_t*> heap; xiaolin
std::deque<node_t*> heap;
};
struct node_t
{
grid_t pos; // position
struct node_t *parent; // parent pointer
int cost; // cost
int total; // total coat (cost + heuristic)
bool onOpen; // open?
bool onClosed; // close?
};
push_heap
template<class RanIt>
void push_heap(RanIt first, RanIt last);
template<class RanIt, class Pred>
void push_heap(RanIt first, RanIt last, Pred pr);
The first template function reorders the sequence designated by iterators in the range [first, last) to form a new heap ordered by operator<. Iterators in the range [first, last - 1) must designate an existing heap, also ordered by operator<. Thus, first != last must be true and *(last - 1) is the element to add to (push on) the heap.
The function evaluates the ordering predicate X < Y ceil(log(last - first)) times, at most.
The second template function behaves the same, except that it replaces operator<(X, Y) with pr(X, Y).
Sample programs: heap and heap (predicate version).
heap (STL Sample)
The sample code below illustrates how to use the heap STL function in Visual C++.
Required Header:
<algorithm>
Prototype:
template<class RandomAccessIterator> inline
void make_heap(RandomAccessIterator first, RandomAccessIterator last)
template<class RandomAccessIterator> inline
void sort_heap(RandomAccessIterator first, RandomAccessIterator last)
template<class RandomAccessIterator> inline
void push_heap(RandomAccessIterator first, RandomAccessIterator last)
template<class RandomAccessIterator> inline
void pop_heap(RandomAccessIterator first, RandomAccessIterator last)
Note: The class/parameter names in the prototype do not match the version in the header file. Some have been modified to improve readability.
Description:
A heap is a sequence of elements organized like a binary tree. Each heap element corresponds to a tree node. The first value in the sequence [first..last) is the root, and is the largest value in the heap. Every element in the heap satisfies the following: Every element is less than or equal to its parent. The largest element is stored in the root, and all children hold progressively smaller values. The make_heap function converts the range [first..last) into a heap. The sort_heap function sorts a "heapified" sequence that was created using the make_heap function. The push_heap function inserts a new value into the heap. The pop_heap function swaps the first and last elements in the heap specified by [first, last), then reduces the length of the sequence by one before restoring the heap property. The non-predicate versions of the heap functions use the operator< for comparisons.
Sample Code:
//////////////////////////////////////////////////////////////////////
//
// Compile options needed: /GX
//
// heap_functions.cpp : Illustrates how to use the
// make_heap, sort_heap, push_heap
// and pop_heap functions.
//
// Functions:
//
// make_heap : convert a sequence to a heap
// sort_heap : sort a heap
// push_heap : insert an element in a heap
// pop_heap : remove the top element from a heap
//////////////////////////////////////////////////////////////////////
// disable warning C4786: symbol greater than 255 character,
// okay to ignore
#pragma warning(disable: 4786)
#include <iostream>
#include <algorithm>
#include <functional>
#include <vector>
using namespace std;
void main()
{
const int VECTOR_SIZE = 8 ;
// Define a template class vector of int
typedef vector<int > IntVector ;
//Define an iterator for template class vector of strings
typedef IntVector::iterator IntVectorIt ;
IntVector Numbers(VECTOR_SIZE) ;
IntVectorIt it ;
// Initialize vector Numbers
Numbers[0] = 4 ;
Numbers[1] = 10;
Numbers[2] = 70 ;
Numbers[3] = 10 ;
Numbers[4] = 30 ;
Numbers[5] = 69 ;
Numbers[6] = 96 ;
Numbers[7] = 100;
// print content of Numbers
cout << "Numbers { " ;
for(it = Numbers.begin(); it != Numbers.end(); it++)
cout << *it << " " ;
cout << " }\n" << endl ;
// convert Numbers into a heap
make_heap(Numbers.begin(), Numbers.end()) ;
cout << "After calling make_heap\n" << endl ;
// print content of Numbers
cout << "Numbers { " ;
for(it = Numbers.begin(); it != Numbers.end(); it++)
cout << *it << " " ;
cout << " }\n" << endl ;
// sort the heapified sequence Numbers
sort_heap(Numbers.begin(), Numbers.end()) ;
cout << "After calling sort_heap\n" << endl ;
// print content of Numbers
cout << "Numbers { " ;
for(it = Numbers.begin(); it != Numbers.end(); it++)
cout << *it << " " ;
cout << " }\n" << endl ;
//insert an element in the heap
Numbers.push_back(7) ;
push_heap(Numbers.begin(), Numbers.end()) ;
// you need to call make_heap to re-assert the
// heap property
make_heap(Numbers.begin(), Numbers.end()) ;
cout << "After calling push_heap and make_heap\n" << endl ;
// print content of Numbers
cout << "Numbers { " ;
for(it = Numbers.begin(); it != Numbers.end(); it++)
cout << *it << " " ;
cout << " }\n" << endl ;
// remove the root element from the heap Numbers
pop_heap(Numbers.begin(), Numbers.end()) ;
cout << "After calling pop_heap\n" << endl ;
// print content of Numbers
cout << "Numbers { " ;
for(it = Numbers.begin(); it != Numbers.end(); it++)
cout << *it << " " ;
cout << " }\n" << endl ;
}
Program Output is:
Numbers { 4 10 70 10 30 69 96 100 }
After calling make_heap
Numbers { 100 30 96 10 4 69 70 10 }
After calling sort_heap
Numbers { 4 10 10 30 69 70 96 100 }
After calling push_heap and make_heap
Numbers { 100 69 96 30 4 70 10 10 7 }
After calling pop_heap
Numbers { 96 69 70 30 4 7 10 10 100 }
typedef int grid_t[2];