https://www.acmicpc.net/problem/14681
if문을 사용하여 a와 b의 양수,음수를 비교한다.
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;
public class Main {
public static void main(String[] args) throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
int a = Integer.parseInt(br.readLine());
int b = Integer.parseInt(br.readLine());
if(a>0) {
if(b>0) {
System.out.println(1);
} else {
System.out.println(4);
}
} else {
if(b>0) {
System.out.println(2);
} else {
System.out.println(3);
}
}
}
}