B"You are given N points on an infinite plane with the Cartesian coordinate system on it. N-1 points lay on one line, and one point isn't on that line. You are on point K at the start, and the goal is to visit every point. You can move between any two points in a straight line, and you can revisit points. What is the minimum length of the path? The first line contains two integers: N ( 3 <= q N <= q 2*10^5 ) - the number of points, and K ( 1 <= q K <= q N ) - the index of the starting point. Each of the next N lines contain two integers, A_i , B_i ( -10^6 <= q A_i, B_i <= q 10^6 ) - coordinates of the i-th point. The output contains one number - the shortest path to visit all given points starting from point K . The absolute difference between your solution and the main solution shouldn't exceed 10^-6 ; The shortest path consists of these moves: 2 -> 5 5 -> 4 4 -> 1 1 -> 3 There isn't any shorter path possible. "...