1561 PRIME

#include<iostream>
#include<cmath>
using namespace std;
int main()
{
   int n;
   cin>>n;
   if(n==1) {
     cout<<2<<endl;
     return 0;
   }
   n=n-1;
   int t=3;
   while(t<=104730){
       bool flag=true;
       for( int i=2;i<=sqrt(t);i++){
          if(t%i==0) flag = false;
          continue;
       }
       if(flag==true) {
           n--;
           if(n==0){
               cout<<t<<endl;
               return 0;
           }
       }
       t=t+2;
   }
}