全排列问题.cpp

经典算法之:连续邮资问题,全排列问题,有限期任务安排,整数划分问题,装载问题

#include <iostream.h>
#define MAX 5
int Q=0;


void Swap(int &a,int &b)
{//Swap a and b.
	int temp =a;
	a=b;
	b=temp;
}

void Perm(int list[],int k,int m)
{//Generate all permutations of list[k:m].
	if((k>m) /*&& (list[m]>list[0])*/)
	{//list[k:m] has one permutation, output it
		for(int i=0;i<=m;i++)
			cout<<list[i];
		cout<<endl;
		Q++;
	}
	else//list[k:m] has more than one permutation
		//generate these recursively
		for(int i=k;i<=m;i++)
		{
			Swap(list[k],list[i]);
			Perm(list,k+1,m);
			Swap(list[k],list[i]);
		}
}

int main()
{
	int list[MAX];
	for(int i=0;i<MAX;i++)
		cin>>list[i];
	Perm(list,0,MAX-1);
	cout<<"Q="<<Q<<endl;
	return 0;
}