https://www.luogu.org/problemnew/show/P3367

//據說根本不用按秩合並，隨機將x合並到y/y合並到x就可以了

 1 // luogu-judger-enable-o2
 2 #include<bits/stdc++.h>
 3 using namespace std;
 4  
 5 #define lop(i,a,b) for(register int i = (a); i <= (b); ++i)
 6 #define getchar() (*p1++)
 7 char buf[3000004],*p1=buf;
 8 const int
 
 N = 10005;
 9 inline int read(){
10        register int c = getchar(), x = 0;
11        while(!isdigit(c)) c = getchar();
12        while(isdigit(c)) x = (x<<3)+(x<<1)+(c^48), c = getchar();
13        return x;
14 }
15 int n, Q, fa[N], ch[300005]; 
16 
17 inline int find(int x){
18     while
 
(x!=fa[x])x=fa[x]=fa[fa[x]];return x;
19 }
20 
21 int main(){
22     fread(buf, 1, 3000000, stdin);
23     n = read(), Q = read();
24     lop(i,1,n)fa[i]=i;
25     while(Q--){
26         int opt = read(), x = read(), y = read();
27         x = find(x), y = find(y);
28         if(opt == 1) fa[x] = y;
 
29                 else puts(x==y?"Y":"N");
30     }
31     return 0;
32 }

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