/* Check cf5-opt.vim defs.
VIM: let g:lcppflags="-std=c++11 -O2 -pthread"
VIM: let g:wcppflags="/O2 /EHsc /DWIN32"
*/
#include <iostream>
#include <vector>

/*
10001st prime
Problem 7

By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13.

What is the 10 001st prime number?

Solution:
104743
*/

typedef std::vector<long long> pt;
pt p;

bool isPrime( long long n )
{
	long h = (long long)sqrt(double(n));
	for ( pt::iterator i = p.begin(), ie = p.end(); 
			i!=ie && *i<=h;
			++i )
		if ( !(n%*i) )
			return false;
	return true;
}

int main ( void )
{
	const long long n = 10001;

	for ( long long i = 2; p.size() < n; ++ i )
		if ( isPrime( i ) )
		   p.push_back( i );
	std::cout << p.back() << std::endl;

	return 0;
}