STL_算法（17）_排列组合 next_permutation() perv_permutation()

next_permutation()

prev_permutation()

#include<iostream>
#include<algorithm>
#include<vector>
// 排列组合开始之前一定要先排序

using namespace std;

int main()
{
vector<int> ivec;

ivec.push_back(1);
ivec.push_back(2);
ivec.push_back(3);

for (vector<int>::iterator iter = ivec.begin(); iter != ivec.end(); iter++)
cout << *iter << ' ';
cout << endl;
//下一个排列组合 该算法返回值为bool 若返回值为true 说明还有下一个排列组合，但是若为fals 说明排列组合已经排列完了
next_permutation(ivec.begin(), ivec.end());
for (vector<int>::iterator iter = ivec.begin(); iter != ivec.end(); iter++)
cout << *iter << ' ';
cout << endl;

while (next_permutation(ivec.begin(), ivec.end()))
{
for (vector<int>::iterator iter = ivec.begin(); iter != ivec.end(); iter++)
cout << *iter << ' ';
cout << endl;
}

cout << endl << endl;
cout << endl << endl;
cout << endl << endl;

vector<int> ivec2;
ivec2.push_back(3);
ivec2.push_back(2);
ivec2.push_back(1);
for (vector<int>::iterator iter = ivec2.begin(); iter != ivec2.end(); iter++)
cout << *iter; ' ';
cout << endl;
//ivec2 本身是个倒序
while (prev_permutation(ivec2.begin(), ivec2.end()))
{
for (vector<int>::iterator iter = ivec2.begin(); iter != ivec2.end(); iter++)
cout << *iter; ' ';
cout << endl;
}

//
system("pause");
return 0;
}