Circle and segment

Find out how manypoints of intersection ofthe circlearegiven bythe centercoordinates (X, Y) and radius R,and the segmentspecified bythe coordinates of itsends (X₁, Y₁), (X₂, Y₂).

Input

SevenintegersX, Y, R, X₁, Y₁, X₂, Y₂, whose moduli do notexceed1000.

Output

The numberof intersection points.