The first line of the input file contains the numbers N and P, and
a real number D, 2 ≤ N ≤ 100, 1 ≤ P ≤ 3000, 1 ≤ D ≤ 10,000.
The number N is the number of towns, the number P is the number of
railroads, and D is the range of the radio in kilometers (a decimal
number two digits precise). The towns are numbered 1 to N. Each of
the following N lines contains data describing one town, i.e. two
integers, X and Y, -5000 ≤ X, Y ≤ 5000, representing the town ’ s
coordinates.
Each of the following P lines contains data describing one railroad
track, i.e. two integers G1 and G2, saying there is a railroad
rack connecting G1 i G2.
The next line contains the starting positions of Mirko and Slavku,
the integers U and V. Mirko starts from town U, Slavko from town V.
U and V will represent two towns separated at most D kilometers
in distance.
