a.cpp

对给定的一个有一定次序任务

#include<iostream.h>
#define maxnode 7
int a[maxnode]={0};
struct node 
{
	int mark;
	node*next;
};
struct Graph
{
	int n,e;
	node graphvertex[maxnode];
};
Graph*creatgraph()
{
	Graph*graph=new Graph;
	if(graph==NULL)
	{
		cout<<"memory is not available"<<endl;
		return NULL;
	}

	cout<<"please put in the node of the graph "<<endl;
	cin>>graph->n;
	cout<<"please put in the edge of the graph"<<endl;
	cin>>graph->e;
	for(int i=0;i<graph->n;i++)
	{
		graph->graphvertex[i].mark=i;
		graph->graphvertex[i].next=NULL;
	}
	for(int j=0;j<graph->e;j++)
	{
		node*temp=new node;
		if(temp==NULL)
		{
			cout<<"no memory available"<<endl;
			return NULL;
		}
	temp->mark=0;
	temp->next=NULL;
	int a,b;
	cout<<"please put in the edge from a to b "<<endl;
	cin>>a>>b;
	temp->mark=b;
	temp->next=graph->graphvertex[a].next;
	graph->graphvertex[a].next=temp;
	}
	return graph;
}
degree(Graph *graph)
{
	node*p;
	for (int i=0;i<graph->n;i++)
	{
		p=graph->graphvertex[i].next;
		while(p)
		{
			a[p->mark]++;
			p=p->next;
		}
		
	}
	for (int j=0;j<graph->n;j++)
		cout<<"the degree of" <<j<<"is"<<a[j]<<endl;
}
int b[maxnode]={0};
int count=0;
push(int i)
{
	if(count<maxnode)
		b[count++]=i;
}
int pop()
{
	if(count>0)
		return b[--count];
}
bool bobuqueue(Graph*graph)
{
	for (int i=0;i<graph->n;i++)
	{
		if(a[i]==0)
			push(i);
	}
	int num=0;
	while(count)
	{
		int j=pop();
		node*p=graph->graphvertex[j].next;
		cout<<j<<"  ";
		num++;
        while(p)
		{
			a[p->mark]--;
			if(a[p->mark]==0)
				push(p->mark);
			p=p->next;
		}
		
	}
	if(num<graph->n)
			return false;
		else 
			return true;
}
	main()
	{
		Graph *graph;
		graph=creatgraph();
		degree(graph);
		bool b;
		b=bobuqueue(graph);
	}