Pairing heap

其实挺好写的。。。(大雾)

理性愉悦大法好。。。

#include<cstdio>
#include<algorithm>
namespace utils{
	template<class T>inline void swp(T&a,T&b){
		T c=a; a=b, b=c;
	}
}using namespace utils;
namespace mempool{
	template<class D,int n=100010>struct pool{
		D p[n],*k,*s[n],**st;
		pool(){
			k=p; st=s;
		}
		inline D*operator()(){
			if(st!=s) return *(--st);
			return k++;
		}
		inline void operator[](D*p){
			*(st++)=p;
		}
	};
}
#define tcd template<class D>
#define pnd PN<D>
namespace PHeap{
	tcd struct PN{
		PN<D>*ch,*pr,*nx;
		D data;
	};
	tcd inline pnd*merge(pnd*a,pnd*b){
		if(!b) return a;
		if(!a) return b;
		if(b->data < a->data) swp(a,b);
		b->nx=a->ch; if(a->ch) a->ch->pr=b;
		a->ch=b; b->pr=a;
		return a;
	}
	tcd inline pnd*cut(pnd*b){
		if(!b)return 0;
		if(b->pr){
			if(b->pr->ch==b) b->pr->ch=b->nx;
			else b->pr->nx=b->nx;
		}
		if(b->nx)b->nx->pr=b->pr;
		b->pr=0,b->nx=0;
		return b;
	}
	tcd inline pnd*decKey(pnd*Root,pnd*node,int amount){
		if(Root==node) return Root->data-=amount,Root;
		node->data-=amount;
		node=cut(node);
		return merge(Root,node);
	}
	tcd inline pnd*Merge_pairing(pnd*fake_root){
		static pnd*Arr[100010],**kh;
		if(!fake_root) return 0;
		int len=0;
		kh=Arr;
		while(fake_root){
			++len;
			*kh=fake_root;
			fake_root=fake_root->nx;
			(*kh)->pr=0; (*kh)->nx=0;
			++kh;
		}
		for(int i=0,_=len&(-2);i<_;i+=2){
			Arr[i]=merge(Arr[i],Arr[i+1]);
		}
		if(len&1) fake_root=Arr[len^1]; else fake_root=0;
		for(int i=(len-2)&(-2);i>=0;i-=2){
			fake_root=merge(fake_root,Arr[i]);
		}
		return fake_root;
	}
	tcd inline pnd*pop(pnd*&heap){
		pnd*r=heap;
		heap=heap->ch;
		if(heap) heap->pr=0;
		r->ch=0;
		heap=Merge_pairing(heap);
		return r;
	}
	tcd inline pnd*show(pnd*k){//whatever you want...
		//the fact is I had written this but I deleted by mistake...
	}
} using namespace PHeap;
namespace debug_suit{
	struct Packaged_int{
		int a,id;
		inline Packaged_int&operator-=(int b){
			return a-=b,*this;
		}
		inline void print(){
			printf("#%d[%d]",id,a);
		}
		inline bool operator<(Packaged_int b){
			return a<b.a;
		}
	};
}using namespace debug_suit;
typedef PN<Packaged_int> PI;
mempool::pool<PI> All;
PI*nodes[100010];
int main(){
	int now=0,d,p,r;
	PI*n,*R;
	char operate[30];
	for(int i=0;i<20;++i){
		nodes[now]=All();
		nodes[now]->data=(Packaged_int){i,now};
		++now;
	}
	for(int i=1;i<20;++i){
		merge(nodes[0],nodes[i]);
	}
	while(~scanf("%s",operate)){
		switch(operate[0]){
			case 'S':
				//show
				scanf("%d",&d);
				show(nodes[d]);
				break;
			case 'N':
				//new
				nodes[now]=All();
				scanf("%d",&d);
				nodes[now]->data=(Packaged_int){d,now};
				++now;
				break;
			case 'I':
				//is root
				scanf("%d",&d);
				printf("%s\n",nodes[d]->pr?"No":"Yes");
				break;
			case 'M':
				scanf("%d%d",&d,&p);
				if(nodes[d]->pr || nodes[p]->pr){
					printf("Not roots, break.\n");
					break;
				}
				R=merge(nodes[d],nodes[p]);
				R->data.print();
				break;
			case 'R':
				scanf("%d%d%d",&d,&p,&r);
				if(p<0){
					printf("p>0\n");
					break;
				}
				if(nodes[r]->pr){
					printf("Not root, break.\n");
					break;
				}
				///no real root checking is performed; A disjoint set is required to do so...
				decKey(nodes[r],nodes[d],p);
				break;
			case 'T':
				scanf("%d",&r);
				if(nodes[r]->pr){
					printf("Not root, break.\n");
					break;
				}
				nodes[r]->data.print();
				break;
			case 'P':
				scanf("%d",&r);
				if(nodes[r]->pr){
					printf("Not root, break.\n");
					break;
				}
				n=nodes[r];
				pop(n);
				printf("New root:\n");
				n->data.print();
				break;
			case 'A':
				printf("Show all\n");
				for(int i=0;i<now;++i) nodes[i]->data.print(),putchar('\n');
				break;
			case 'Q':
				return 0;
		}
	}
	return 0;
}