partition (STL Samples)
在 Visual C++ 演示如何使用 分区 标准 (STL)模板库函数。
template<class BidirectionalIterator, class Predicate> inline
BidirectionalIterator partition(
BidirectionalIterator First,
BidirectionalIterator Last,
Predicate Predicate
)
备注
备注
类/参数名在原型不匹配版本在头文件。修改某些提高可读性。
分区 算法对该范围 [First， Last) 的元素会 Predicate 返回 true 是在元素之前谓词为其返回 错误的元素。 算法返回迭代器确定在 Predicate 返回 错误的第一个元素。
示例
// partition.cpp
// compile with: /EHsc
// Illustrates how to use the partition function.
//
// Functions:
// partition - Partition a range using a predicate.
//
// begin - Returns an iterator that points to the first element
// in a sequence.
//
// end - Returns an iterator that points one past the end of
// a sequence.
//
// bind2nd - Returns true for elements for which the condition
// is true.
// disable warning C4786: symbol greater than 255 character,
// okay to ignore
#pragma warning(disable: 4786)
#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>
using namespace std;
int main()
{
const int VECTOR_SIZE = 8 ;
// Define a template class vector of integers
typedef vector<int > IntVector ;
//Define an iterator for template class vector of integer
typedef IntVector::iterator IntVectorIt ;
IntVector Numbers(VECTOR_SIZE) ; //vector containing numbers
IntVectorIt start, end, it ;
start = Numbers.begin() ; // location of first
// element of Numbers
end = Numbers.end() ; // one past the location
// last element of Numbers
//Initialize vector Numbers
Numbers[0] = 6 ;
Numbers[1] = 20 ;
Numbers[2] = 10 ;
Numbers[3] = 15 ;
Numbers[4] = 12 ;
Numbers[5] = 7 ;
Numbers[6] = 9 ;
Numbers[7] = 10 ;
cout << "Before calling partition" << endl ;
// print content of Numbers
cout << "Numbers { " ;
for(it = start; it != end; it++)
cout << *it << " " ;
cout << " }\n" << endl ;
// partition the sequence such that all the elements
// less than 11 appear before all the elements greater than 11
it = partition(start, end, bind2nd(less<int>(), 11)) ;
cout << "After calling partition" << endl ;
// print content of Numbers
cout << "Numbers { " ;
for(it = start; it != end; it++)
cout << *it << " " ;
cout << " }\n" << endl ;
}
Output
Before calling partition
Numbers { 6 20 10 15 12 7 9 10 }
After calling partition
Numbers { 6 10 10 9 7 12 15 20 }
要求
**标题:**algorithm