poj 1691

dfs

代码：

#include<iostream>
#include<fstream>

using namespace std;

int n;

struct e{
	int x1,y1,x2,y2,c;
};

e a[16];

struct ee{
	int data;
	ee *next;
};

ee edge[16];
int ans;
int d[16];
int v[16];

void solve(int num,int value,int color){
	int i,j,k;
	if(value>ans) return;
	if(num==n)
	{
		ans=value;
		return;
	}
	for(i=1;i<=n;i++)
	{
		if(d[i]==0&&v[i]==0)
		{
			v[i]=1;
			ee *p=edge[i].next;
			while(p){
				d[p->data]--;
				p=p->next;
			}
			if(color!=a[i].c) solve(num+1,value+1,a[i].c);
			else solve(num+1,value,color);
			p=edge[i].next;
			while(p)
			{
				d[p->data]++;
				p=p->next;
			}
			v[i]=0;
		}
	}
}


void build(){
	int i,j,k;
	for(i=1;i<=n;i++)
	{
		edge[i].data=i;
		edge[i].next=0;
	}
	for(i=1;i<=n;i++)
		for(j=1;j<=n;j++)
		{
			if(a[j].x1==a[i].x2&&((a[i].y1>=a[j].y1&&a[i].y1<a[j].y2)||(a[j].y1>=a[i].y1&&a[j].y1<a[i].y2)))
			{
				ee *p=new ee;
				p->data=j;
				p->next=edge[i].next;
				edge[i].next=p;
				d[j]++;
			}
		}
}

void read(){
//	ifstream cin("in.txt");
	int i,j,k;
	int cas;
	cin>>cas;
	while(cas--)
	{
		
		memset(d,0,sizeof(d));
		memset(v,0,sizeof(v));
		cin>>n;
		ans=n+1;
		for(i=1;i<=n;i++)
			cin>>a[i].x1>>a[i].y1>>a[i].x2>>a[i].y2>>a[i].c;
		build();
		solve(0,0,0);
		cout<<ans<<endl;
	}
	
}

int main(){
	read();
	return 0;
}

转载于:https://www.cnblogs.com/zhaozhe/archive/2011/05/12/2044320.html