Predicate Version of next_permutation

在 Visual C++ 演示如何使用 next_permutation 标准模板库函数的 (STL)谓词版本。

template<class BidirectionalIterator, class Compare> inline
   bool next_permutation(
      BidirectionalIterator First,
      BidirectionalIterator Last,
      Compare Compare
   )

备注

说明
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。

next_permutation 算法更改元素的顺序在范围 [First， Last) 的一个字典数组和返回 true。如果没有 next_permutation，它使该序列是第一个数组和返回 错误。

说明
next_permutation 算法假定使用 比较 功能，，顺序按升序排序。nonpredicate 版本使用 比较 功能顺序排列。

示例

// next_permutationPV.cpp
// compile with: /EHsc
// Illustrates how to use the predicate version
// of the next_permutation function.
//
// Functions:
//    next_permutation : Change the order of the sequence to the
//                       next lexicograhic permutation.

// disable warning C4786: symbol greater than 255 character,
// okay to ignore
#pragma warning(disable: 4786)

#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <functional>

using namespace std ;

int main()
{
    const int VECTOR_SIZE = 3 ;

    // Define a template class vector of strings
    typedef vector<string> StrVector ;

    //Define an iterator for template class vector of strings
    typedef StrVector::iterator StrVectorIt ;

    //Define an ostream iterator for strings
    typedef ostream_iterator<string> StrOstreamIt;

    StrVector Pattern(VECTOR_SIZE);

    StrVectorIt start, end, it;

    StrOstreamIt outIt(cout, " ");

   // location of first element of Pattern
    start = Pattern.begin();

   // one past the location last element of Pattern
    end = Pattern.end();

    // Initialize vector Pattern
    Pattern[0] = "K" ;
    Pattern[1] = "A" ;
    Pattern[2] = "L" ;

    // sort the contents of Pattern, required by next_permutation
    sort(start, end, less<string>()) ;

    // print content of Pattern
    cout << "Before calling next_permutation..." << endl << "Pattern:" ;
    for (it = start; it != end; it++)
        cout << " " << *it;
    cout << endl;

    // Generate all possible permutations

    cout << "After calling next_permutation...." << endl;
    while ( next_permutation(start, end, less<string>()) )
    {
        copy(start, end, outIt) ;
        cout << endl ;
    }
}

示例输出

Before calling next_permutation:
Pattern: A K L

After calling next_permutation:.
A L K
K A L
K L A
L A K
L K A

要求

**标题:**algorithm

请参见

概念

标准模板库示例