C++ 알고리즘 - 백준 1929 소수 구하기 (에라토스테네스의 체)

https://www.acmicpc.net/problem/1929

 

#include <bits/stdc++.h>
#define endl "\n"

using namespace std;

int num[1000001];

int main(void)
{
     // C++ Init
     ios::sync_with_stdio(false);
     cin.tie(NULL);

     int input1, input2;
     cin >> input1 >> input2;

     for (int i = 2; i < 1000001; i++)
     {
          num[i] = i;
     }

     for (int i = 2; i <= 1000; i++)
     {
          if (num[i] == 0)
               continue;

          for (int j = i * i; j <= 1000001; j += i)
               num[j] = 0;
     }

     for (int i = input1; i <= input2; i++)
     {
          if (num[i] != 0)
               cout << num[i] << endl;
     }
}