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);
}