#include<cstdio>
int n,prime[1000001],tot;
bool mark[1000001];
int main(){
	scanf("%d",&n);
	for(int i=2;i<=n;i++){
		if(!mark[i])prime[++tot]=i;
		for(int j=1;j<=tot&&i*prime[j]<=n;j++){
			mark[prime[j]*i]=true;
			if(i%prime[j]==0)break;
		}
	}
}