How many points in common two given circles have?

Input

Six real numbers x1, y1, r1, x2, y2, r2, where x1, y1, x2, y2 are the coordinates of the centers of the circles, r1, r2 are its radius.

Output

The number of common points for two circles: 0, 1 or 2. Print -1 if circles have a lot of common points.