/**
 * @(#)Angles.java
 *
 *
 * @author 
 * @version 1.00 2009/11/25
 */

import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.PrintWriter;

public class Angles {

    public static void main(String args[]) throws IOException{
    	BufferedReader br = new BufferedReader(new FileReader("Data1.txt"));
    	PrintWriter pw = new PrintWriter(new FileWriter("Out1.txt"));
    	String line;
    	String[] parts = new String[4];
    	double[] num = new double[4];
    	double a1, a2, angle;
    	
    	for(int i = 0; i < 5; i++) {
    		line = br.readLine();

    		if (line == null)
    			break;
    			
    		parts = line.split("\\s");
    		
    		
    		for (int j = 0; j < 4; j++)
    			num[j] = Double.parseDouble(parts[j]);
    		
    		a1 = Math.atan(num[1] / num[0]);
    		if (num[1] >= 0) {
    			if (num[0] < 0)
    				a1 += Math.PI;
       		} else {
    			if (num[0] >= 0)
    				a1 = a1 + 2 * Math.PI;
    			else
    				a1 += Math.PI;
    			
    		}
    		
    		a2 = Math.atan(num[3] / num[2]);
    		
    		if (num[3] >= 0) {
    			if (num[2] < 0)
    				a2 += Math.PI;
    			
    		} else {
    			if (num[2] >= 0)
    				a2 += 2 * Math.PI;
    			else
    				a2 += Math.PI;
    		}
			
			angle = Math.toDegrees(a1-a2);
			
			if (angle < 0) 
				angle += 360;
		
    		pw.println(angle);
    	}
    	
    	pw.close();
    	br.close();	
    }
    
}