Joint search set: the number of points in connected blocks (the number of points in a set)

#include<iostream>
using namespace std;

const int N=100010;

int n,m;
int p[N];
int size[N]; 

// return x The ancestor node of + Path compression 
// Path compression ： Point each node to its ancestor node  
int find(int x)
{
	if(p[x]!=x)
		p[x]=find(p[x]);
	return p[x];
}

int main()
{
	scanf("%d%d",&n,&m);
	
	// initialization ： Point the ancestor node of each node to itself  
	for(int i=1;i<=n;i++)
	{
		p[i]=i;
		size[i]=1;
	}
	
	while(m--)
	{
		char op[5];
		int a,b;
		scanf("%s",op);
		if(op[0]=='C')// Merge nodes   
		{
			scanf("%d%d",&a,&b);
			if(find(a)==find(b))
				continue;
			size[find(b)]+=size[find(a)];
			p[find(a)]=find(b);
		}
		else if(op[1]=='1')
		{
			scanf("%d%d",&a,&b);
			if(find(a)==find(b))
				puts("Yes");
			else
				puts("No");
		}
		else
		{
			scanf("%d",&a);
			printf("%d\n",size[find(a)]);
		}
	}
	
	return 0;
}