signclass.java

非常好的JAVA学习资料

import java.io.*;
public class SignClass
{
   public static void main(String args[]) throws IOException
   {
      double x;
      int y;
      String str;
      BufferedReader buf;
      buf=new BufferedReader(new InputStreamReader(System.in));
      System.out.print("Input x is:");
      str=buf.readLine();        
      x=Double.parseDouble(str);    
      if (x>0)
          y=1;  
     else if (x==0)
          y=0;
     else
          y=-1;
   System.out.print("y="+y);  
   }
}