第二题
#include<iostream>
#include <string>
using namespace std;


//int a, b, c;
//cin >> a >> b >> c;
//int res;
//res = 1 + b - c;
//cout << res;
//return (0);

int array1[1001];
int array2[1001];
int main()
{
    int n;
    cin >> n;
    if (n <= 1)
    {
        cout << 0 << endl;
        return 0;
    }
    for (int i = 0; i < 1001; i++)
    {
        array1[i] = array2[i] = 0;
    }
    //int *array1 = new int[n + 1]{0};
    /*计算素数*/
    //int *array2 = new int[n + 1]{0};
    for (int i = 2; i <= n; i++)
    {
        if (array2[i] == 0)
        {
            for (int j = 2; j*i <= n;j++)
            {
                array2[j*i] = 1;
            }
        }
        if (array2[i] == 1)
        {
            continue;
        }
    }
    /*方幂*/
    for (int i = 2; i <= n; i++)
    {
        if (array2[i] == 0)
        {
            array1[i] = 1;
            //int j = 1;
            int base = i;
            int temp = i;
            while (1)
            {
                temp *= base;
                if (temp > n)
                {
                    break;
                }
                else
                {
                    array1[temp] = 1;
                }
            }
        }
        else
        {
            continue;
        }
    }
    int cnt = 0;
    for (int i = 2; i <= n; i++)
    {
        if (array1[i]==1)
        {
            cnt++;
        }
    }
    //delete[] array1;
    //delete[] array2;
    return (0);
}