A point (x,y), on the cartesian plane, makes an angle theta with the positive direction of the x-axis. Theta varies in the interval [0 ,2PI) radians, i.e, greater than or equal to zero; but less than 2*PI radians.

For example, the polar angle of the point (1,2) as marked in this plane below, is (approximately) 63.4 degrees (multiply by PI/180 to convert to radians)

Ref http://eldar.mathstat.uoguelph.ca/dashlock/Outreach/Articles/images/PRfig1.jpg

The Task

Given a list of points in the 2D plane, sort them in ascending order of their polar angle. In case multiple points share exactly the same polar angle, the one with lesser distance from the origin (0,0) should occur earlier in the sorted list.

Input Format
The first line contains an integer N.
This is followed by N lines containing pairs of space separated integers, x and y which represent the coordinates of the points in the cartesian plane.

Constraints
1 <= N <= 1000
-100 <= x,y <= 100
The point (0,0) will not be present in the list of points.

Output Format
The output should contain N lines. Each line should contain two integers x and y, corresponding to a point in the original list. Display the points in ascending order of their polar angle.

Sample Input

4  
1 0  
0 -1  
-1 0  
0 1  

Sample Output

1 0    
0 1    
-1 0    
0 -1    

Explanation

The point (0,1) has a polar angle of 90 degrees. The point (1,0) has a polar angle of 0 degrees. (-1,0) has a polar angle of 180 degrees and (0,-1) has a polar angle of 270 degrees.