2811 : 소수와 합성수

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.StringTokenizer;
 
public class Main {
 
    public static void main(String[] args) throws IOException {
        // TODO Auto-generated method stub
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(in.readLine());
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
     
        int number[] = new int [6];
        int i, j;
         
        for (i = 0; i < 5; i++) {
            number[i] = Integer.parseInt(st.nextToken());
        }
             
        for (i = 0; i < 5; i++) {
            if (number[i]==1){
                bw.write("number one\n");
            }
            else if (isPrime(number[i])) {
                bw.write("prime number\n");             
            }
            else {
                bw.write("composite number\n");
            }
            bw.flush();
             
        }
         
    }
     
    public static boolean isPrime(int num) {
        if(num<2) return false;
        for(int i=2;i<=Math.sqrt(num);i++) {
            if(num%i==0) return false;
        }
        return true;
    }
}

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