next_permutation就是按字典序进行下一次排列

int main()
{
int num[3]={1,2,3};
do
{
cout<<num[0]<<” “<<num[1]<<” “<<num[2]<<endl;
}while(next_permutation(num,num+3));

结果是   1 2 3
         1 3 2
         2 1 3
         2 3 1
         3 1 2
         3 2 1