#include <cstdio>#include <iostream>#include <algorithm>#define N 20001int prime[N];bool not_prime[N];int n, cnt, ans, num;inline int read(){	int x = 0, f = 1;	char ch = getchar();	for(; !isdigit(ch); ch = getchar()) if(ch == ‘-‘) f = -1;	for(; isdigit(ch); ch = getchar()) x = (x << 1) + (x << 3) + ch - ‘0‘;	return x * f;}inline void init(){	int i, j;	for(i = 2; i < N; i++)		if(!not_prime[i])		{			prime[++cnt] = i;			for(j = i + i; j < N; j += i) not_prime[j] = 1;		}}int main(){	int i, j, a, x;	init();	n = read();	for(i = 1; i <= n; i++)	{		a = read();		x = std::upper_bound(prime + 1, prime + cnt + 1, a) - prime;		for(j = x - 1; j >= 1; j--)			if(a % prime[j] == 0)			{				if(prime[j] > num || (prime[j] == num && a > ans))				{					num = prime[j];					ans = a;				}				break;			}	}	printf("%d\n", ans);	return 0;}

#include <cstdio>#include <iostream>int n;inline int read(){	int x = 0, f = 1;	char ch = getchar();	for(; !isdigit(ch); ch = getchar()) if(ch == ‘-‘) f = -1;	for(; isdigit(ch); ch = getchar()) x = (x << 1) + (x << 3) + ch - ‘0‘;	return x * f;}int main(){	n = read();	printf("%d\n", n / 3 * 2 + (n % 3 == 2));	return 0;}