49pts,不知道错在哪里，hack一下也行

#include<bits/stdc++.h>

using namespace std;

inline int read(){
    int u=0,f=1;char ch=getchar();
    while (ch<'0'||ch>'9'){if(ch=='-') f=-1;ch=getchar();}
    while (ch>='0'&&ch<='9'){u=u*10+ch-48;ch=getchar();}
    return u*f;
}
struct node{
	int x1,y1,x2,y2,c,tag;
};
node a[50500];
int n,ans=1e9,numc;
int vis[5005];
vector<int>vec[5005];
inline bool check(int i){//判断能否染色
	for(auto v:vec[i]){
		if(!vis[v])return 0;
	}
	return 1;
}
inline void dfs(int step,int res){//刷子改变次数，还剩下几个方块
	if(step>ans)return;//剪枝
	if(step>n)return;//剪枝
	if(res==0){
		ans=min(ans,step-1);
		return;
	}
	for(int i=1;i<=numc;i++){
		int q=0;
		for(int j=1;j<=n;j++){
			if(a[j].c!=i)continue;
			if(vis[j])continue;
			if(check(j)){
				vis[j]=step;
				q++;
			}
		}
		if(q==0)continue;//剪枝
		dfs(step+1,res-q);
		for(int j=1;j<=n;j++){//回溯
			if(a[j].c!=i)continue;
			if(vis[j]==step){
				vis[j]=0;
			}
		}
	}
}
inline bool cmp(node x,node y){
	if(x.y1==y.y1)return x.x1<y.x1;
	return x.y1<y.y1;
}
signed main(){
	n=read();
	for(int i=1;i<=n;i++){
		a[i].y1=read();
		a[i].x1=read();
		a[i].y2=read();
		a[i].x2=read();
		a[i].c=read();
		numc=max(numc,a[i].c);
	}
	sort(a+1,a+1+n,cmp);
	/*for(int i=1;i<=n;i++){
		printf("%d %d %d %d %d\n",a[i].y1,a[i].x1,a[i].y2,a[i].x2,a[i].c);
	}*/
	for(int i=1;i<=n;i++){//预处理是不是前置方块
		if(a[i].y1!=0){
			for(int j=1;j<=n;j++){
				if(i==j)continue;
				if(a[i].y1==a[j].y1)break;
				if(a[j].y2==a[i].y1){
					if(a[j].x1<a[i].x2||a[j].x2>a[i].x1){
						vec[i].push_back(j);
					}
				}
			}
		}
	}
	/*for(int i=1;i<=n;i++){
		for(auto v:vec[i])printf("%d ",v);
		printf("\n");
	}*/
	dfs(1,n);
	cout<<ans<<endl;
	return 0;
}