并查集 UVA11987 带删除并查集

I hope you know the beautiful Union-Find structure. In this problem, you’re to implement something similar, but not identical. The data structure you need to write is also a collection of disjoint sets, supporting 3 operations: 1 p q Union the sets containing p and q. If p and q are already in the same set, ignore this command. 2 p q Move p to the set containing q. If p and q are already in the same set, ignore this command. 3 p Return the number of elements and the sum of elements in the set containing p. Initially, the collection contains n sets: {1}, {2}, {3}, . . . , {n}.

Input

There are several test cases. Each test case begins with a line containing two integers n and m (1 ≤ n, m ≤ 100, 000), the number of integers, and the number of commands. Each of the next m lines contains a command. For every operation, 1 ≤ p, q ≤ n. The input is terminated by end-of-file (EOF).

Output

For each type-3 command, output 2 integers: the number of elements and the sum of elements.

Explanation

Initially: {1}, {2}, {3}, {4}, {5}

Collection after operation 1 1 2: {1,2}, {3}, {4}, {5}

Collection after operation 2 3 4: {1,2}, {3,4}, {5} (we omit the empty set that is produced when taking out 3 from {3})

Collection after operation 1 3 5: {1,2}, {3,4,5}

Collection after operation 2 4 1: {1,2,4}, {3,5}

Sample Input

5 7

1 1 2

2 3 4

1 3 5

3 4

2 4 1

3 4

3 3

Sample Output

3 12

3 7

2 8

 

主要问题出现在2move操作,有可能移动的是根节点,只要是有儿子的节点就很麻烦。那我们怎样解决这个问题呢?

所有的问题都可以依靠再开某些记录意义的数组解决(大雾

So,我们用一个id[i]数组记录进行移动的节点的父亲的真正标号,至于p[i]本身仍然作为一个编号一个父节点留在原处。

要注意每次调用find函数时,find的变量不再是x而是id[x]!

(需要再好好理解感受一下hiahiahiahia

 

#include 

const int maxnm=100010;

int n,m;
int p[maxnm],cnt[maxnm],id[maxnm];	//标记编号
long long sum[maxnm];
int c,x,y,fx,fy;

int find(int x)
{
	return x==p[x]?x:p[x]=find(p[x]);
}

int main()
{
	while(~scanf("%d%d",&n,&m)){
		for(int i=1;i<=n;++i){
			p[i]=sum[i]=id[i]=i;
			cnt[i]=1;
		}
		for(int i=0;i

 

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