Submission

Score: 100

User: Jokul

Problemset: ส่งต่อ

Language: cpp

Time: 0.003 second

Submitted On: 2025-09-18 08:19:16

#include <iostream>
using namespace std;
int main(){
	int n,s,count=0;
	cin>> n;
	cin>> s;
	int a[n+1],b[n+1];
	for(int i=0;i<=n;i++)
	{
		a[i]=0;
	}
	b[0]=0;
	for(int i=1;i<=n;i++)
	{
		cin>> b[i];
	}
	a[s]=1;
	for(int i=0;i<n;i++)
	{
		//	cout<< "1.  "<<b[s] << endl;
			if(b[s]!=0&&a[b[s]]<1)
			{
			a[b[s]]++;
			//cout<<" 2.  " <<a[b[s]] << endl;
			s=b[s];
			// cout<<"3." << s <<endl;
		    }
		    else
		    {
		    	break;
			}

	}
	for(int i=0;i<=n;i++)
	{
		count=count+a[i];
	}
	cout<< count << endl;
	
}