C++ STL algorithm, sort_heap() code example
Compiler: Visual C++ Express Edition 2005
Compiled on Platform: Windows XP Pro SP2
Header file: Standard
Additional project setting: Set project to be compiled as C++
Project -> your_project_name Properties -> Configuration Properties -> C/C++ -> Advanced -> Compiled As: Compiled as C++ Code (/TP)
Other info: none
To do: Using the sort_heap() to convert a heap into a sorted range in C++ programming
To show: How to use the C++ algorithm, sort_heap() member to convert a heap into a sorted range in C++ programming
// C++ STL algorithm, sort_heap()
// compiled with /EHsc flag
#include <vector>
#include <algorithm>
#include <functional>
#include <iostream>
using namespace std;
int main(void)
{
// vector container
vector <int> vec1;
// vector iterator
vector <int>::iterator Iter1, Iter2;
int i = 0;
// push data into the vector container
for(i = 1; i <= 10; i++)
vec1.push_back(i);
// print the data
cout<<"Original vec1 vector data: ";
for(Iter1 = vec1.begin(); Iter1 != vec1.end(); Iter1++)
cout<<*Iter1<<" ";
cout<<endl;
random_shuffle(vec1.begin(), vec1.end());
cout<<"\nRandom shuffle vec1 vector data: ";
for(Iter1 = vec1.begin(); Iter1 != vec1.end(); Iter1++)
cout<<*Iter1<<" ";
cout<<endl;
// make vec1 a heap with default less-than ordering
make_heap(vec1.begin(), vec1.end());
cout<<"\nThe default less-than heaped version of vec1 vector data: ";
for(Iter1 = vec1.begin(); Iter1 != vec1.end(); Iter1++)
cout<<*Iter1<<" ";
cout<<endl;
// note: without default less-than ordering make_heap() called, the following
// sort_heap() default less-than ordering will generate invalid heap error but it
// is OK for sort_heap() with greater than ordering...BUG???
//
// sort heap vec1 with default less-than ordering
sort_heap(vec1.begin(), vec1.end());
cout<<"\nThe sorted heap vec1 vector data: ";
for(Iter1 = vec1.begin(); Iter1 != vec1.end(); Iter1++)
cout<<*Iter1<<" ";
cout<<endl;
// make vec1 a heap with greater than ordering
make_heap(vec1.begin(), vec1.end(), greater<int>());
cout<<"\nThe greater than heaped version of vec1 vector data: ";
for(Iter1 = vec1.begin(); Iter1 != vec1.end(); Iter1++)
cout<<*Iter1<<" ";
cout<<endl;
sort_heap(vec1.begin(), vec1.end(), greater<int>());
cout<<"\nThe greater than sorted heap vec1 vector data:";
for(Iter1 = vec1.begin(); Iter1 != vec1.end(); Iter1++)
cout<<*Iter1<<" ";
cout<<endl;
return 0;
}
Output examples:
Original vec1 vector data: 1 2 3 4 5 6 7 8 9 10
Random shuffle vec1 vector data: 9 2 10 3 1 6 8 4 5 7
The default less-than heaped version of vec1 vector data: 10 7 9 5 2 6 8 4 3 1
The sorted heap vec1 vector data: 1 2 3 4 5 6 7 8 9 10
The greater than heaped version of vec1 vector data: 1 2 3 4 5 6 7 8 9 10
The greater than sorted heap vec1 vector data:10 9 8 7 6 5 4 3 2 1
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