You are given four points and in a 3-dimensional Cartesian coordinate system. You are required to print the angle between the plane made by the points and in degrees(not radians). Let the angle be .

where x and x .

Here, means the dot product of and , and x means the cross product of vectors and . Also, .

Input Format

One line of input containing the space separated floating number values of the and coordinates of a point.

Output Format

Output the angle correct up to two decimal places.

Sample Input

0 4 5
1 7 6
0 5 9
1 7 2

Sample Output

8.19