Problems
Two circles
Two circles
How many points in common two given circles have?

Input data
Six real numbers x_1, y_1, r_1, x_2, y_2, r_2, where x_1, y_1, x_2, y_2 are the coordinates of the centers of the circles, r_1, r_2 are its radius.
Output data
The number of common points for two circles: 0, 1 or 2. Print -1 if circles have a lot of common points.
Examples
Input example #1
0 0 5 5 0 1
Output example #1
2