并查集模板

Posted 2020-08-12 fuyun_boy

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<algorithm>
 5 using namespace std;
 6 
 7 int N,M,fa[10005];
 8 int find(int );
 9 
10 void pt(int x,int y)
11 {
12     int faa=find(x);
13     int fbb=find(y);
14     if(faa==fbb)printf("Y\n");
15     else printf("N\n");
16 }
17 
18 int find(int x)
19 {
20     int r=x;
21     while( fa[r]!=r )r=fa[r];
22     while(x!=r){
23         x=fa[x];
24         fa[x]=r;
25     }
26     return r;
27 }
28 
29 void ADD( int X , int Y )
30 {
31     int faa=find(X);
32     int fbb=find(Y);
33     if( faa != fbb ){
34         fa[faa]=fbb;
35     }
36 }
37 
38 void init()
39 {
40     int X,Y,Z;
41     cin>>N>>M;
42     for(int i=1;i<=N;i++){
43         fa[i]=i;
44     }
45     for(int j=1;j<=M;j++){
46         scanf("%d%d%d",&Z,&X,&Y);
47         if(Z==1)ADD( X , Y );
48         if(Z==2)pt( X , Y );
49     }
50 }
51 
52 int main()
53 {
54     init();
55     return 0;
56 }

洛谷3367：http://www.luogu.org/problem/show?pid=3367