CF1599G Shortest path

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 \leq N \leq 2*10^5 $ ) - the number of points, and $ K $ ( $ 1 \leq K \leq N $ ) - the index of the starting point. Each of the next $ N $ lines contain two integers, $ A_i $ , $ B_i $ ( $ -10^6 \leq A_i, B_i \leq 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.