TLE on #4#5求条

12345678910111213#include <iostream>
using namespace std;
int main(){
    int n,cnt=0;
    cin>>n;
    for(int i=2;i<=n;i++){
        int is=1;
        for(int j=2;j<i;j++){if(i%j==0) is=0;}
        cnt+=is;
    }
    cout<<cnt;
    return 0;
}