#include<iostream>
using namespace std;
long n,s=0,i;
bool f=true;
int main(){
	cin>>n;
	for(i=2;;i++){
		f=true;
		for(int j=2;j*j<=i;j++) if(i%j==0) f=false;
		if(f) s++;
		if(s==n) break;
	}
	cout<<i<<"\n";
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
int x[10001]={0,1,2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,179,181,191,193,197,199,211,223,227,229,233,239,241,251,257,263,269,271,277,281,283,293,307,311,313,317,331,337,347,349,353,359,367,373,379,383,389,397,401,409,419,421,431,433,439,443,449,457,461,463,467,479,487,491,499,503,509,521,523,541,547,557,563,569,571,577,587,593,599,601,607,613,617,619,631,641,643,647,653,659,661,673,677,683,691,701,709,719,727,733,739,743,751,757,761,769,773,787,797,809,811,821,823,827,829,839,853,857,859,863,877,881,883,887,907,911,919,929,937,941,947,953,967,971,977,983,991,997,1009,1013,1019,1021,1031,1033,1039};
int main(){
	int n;
	cin>>n;
	cout<<x[n+1];
	return 0;
}//致敬传奇打表王，可惜过不了，没读取道过程（没过程）。

#include <bits/stdc++.h>
using namespace std;
int main(int argc, char **argv){
	int n,zhi = 2;
	cin >> n;
	while (true){
		bool flag = 1;
		for (int i = 2;i < zhi;i++){
			if (i > 10000){
				i *= i;
			}
			if (zhi % i == 0){
				flag = 0;
				break;
			}
		}
		if (flag){
			n--;
		}
		if (n == 0){
			break;
		}
		zhi++;
	}
	cout << zhi;
	return 0;
}
//2 3 5 7 11 13 17 19 23 29

#include <bits/stdc++.h>
using namespace std;
int main(){
	int n,i;
	cin>>n;
	for(i=2;;i++){
		int a=1;	
		for(int j=2;j*j<=i;j++){
			if(i%j==0){
				a=0;
				break;
			}
		}
		if(a==1){
			n--;	
			if(n==0) break;
		}
	}
	cout<<i<<endl;
	return 0;
}

#include <bits/stdc++.h>

using namespace std;

int main()

{

int n,i;

cin>>n;

for( i=2;;i++)

{

int a=1;

for(int j=2;j*j<=i;j++)

{

if(i%j==0)

{

a=0;

break;

}

}

if(a==1)

{

n--;

if(n==0) break;

}

}

cout<<i;

}

//点个赞吧！——李尤

#include<bits/stdc++.h>
using namespace std;
bool f;
long long a;
short n,sum=1;
long long fn(int x){
   for(int i=2;i<=INT_MAX;i++){
      for(int k=2;k<i/2;k++){
         if(i%k==0){
            f=0;
            break;}
      }
      if(f==1){
         a=i;
         sum++;
         f=0;
         if(sum==x) return a;
      }else f=1;
   }
   return 0;
}
int main(){
   cin>>n;
   cout<<fn(n);
   return 0;
}

#include<bits/stdc++.h>
using namespace std;
bool sushu(int n){//判断n是否为质数
    if(n<2) return false;//如果n<2 返回假
    for(int i=2;i<=sqrt(n);i++){
        if(n%i==0) return false;//如果n%i余数是0,说明n不是质数,返回假
    }
    return true;//排除前两项,说明它是质数,返回真
}
int main(){
    int n,sum=0;
    cin>>n;
    for(int i=1;i>=1;i++){//循环遍历所有数
        if(sushu(i)==true){//如果是质数
            sum++;//就计数（贮存当前是第几个质数）
        }
         if(sum==n){//如果是第n小的质数,输出这个质数
                cout<<i;
                return 0;
            }
    }
    return 0;
}

#include<bits/stdc++.h> using namespace std; int main(){ long long n,a=0,s=0,i; cin>>n; for(i=2; ;i++){ a=0; for(int j=2;j*j<=i;j++){ if(i%j0){ a=1; break; } } if(a0){ s++; } if(s==n){ break; } } cout<<i; }