B'Two friends are travelling through Bubble galaxy. They say "Hello!" via signals to each other if their distance is smaller or equal than d_1 and We need to calculate how many times friends said "Hello!" to each other. For N moments, you 'll have an array of points for each friend representing their positions at that moment. A person can stay in the same position between two moments in time, but if a person made a move we assume this movement as movement with constant speed in constant direction. The first line contains one integer number N ( 2 <= q N <= q 100 ,000 ) representing number of moments in which we captured positions for two friends. The second line contains two integer numbers d_1 and d_2 (0 < d_1 < d_2 < 1000) . The next N lines contains four integer numbers A_x,A_y,B_x,B_y ( 0 <= q A_x, A_y, B_x, B_y <= q 1000 ) representing coordinates of friends A and B in each captured moment. Output contains one integer number that represents how many times friends will say "Hello!" to each other. Explanation: Friends should send signals 2 times to each other, first time around point A2 and B2 and second time during A 's travel from point A3 to A4 while B stays in point B3=B4 . '...