[백준][Java] 1929번 소수 구하기 (에라토스테네스의 체)

[백준][Java] 1929번 소수 구하기 (에라토스테네스의 체)

import java.io.BufferedReader;

import java.io.BufferedWriter;

import java.io.IOException;

import java.io.InputStreamReader;

import java.io.OutputStreamWriter;

public class Main {

private static BufferedReader br = new BufferedReader( new InputStreamReader( System . in ));

private static BufferedWriter bw = new BufferedWriter( new OutputStreamWriter( System . out ));

public static void main( String [] args) throws IOException{

String [] str = br.readLine(). split ( " " );

boolean [] prime = new boolean [ 1000001 ];

prime[ 0 ] = prime[ 1 ] = true ;

int A = Integer. parseInt (str[ 0 ]);

int B = Integer. parseInt (str[ 1 ]);

for ( int i = 2 ; i * i < = B; i + + ) {

if ( ! prime[i]) {

for ( int j = i * i; j < = B; j + = i) {

prime[j] = true ;

}

}

}

for ( int i = A; i < = B; i + + ){

if ( ! prime[i]) System . out . println (i);

}

// bw.write("");

// bw.flush();

// bw.close();

}

}

from http://aig2029.tistory.com/274 by ccl(A) rewrite - 2021-09-12 04:01:15