For a promotional stunt, Antu picks the K bus stops closest to the depot (by straight-line distance) and wants to know if all K stops can be visited via short connecting hops (distance ≤ D) without leaving any stop stranded. Given N 2D points and integer K, first find the K points closest to the origin (Euclidean distance). Then, treating those K points as nodes fully connected to each other (edge exists if Euclidean distance ≤ D, a given threshold), print "YES" if all K points form a single connected component, else "NO".
Input
Line1: N K D. Next N lines: x y.
Output
"YES" or "NO".
Constraints
1 ≤ K ≤ N ≤ 2000
Sample Input
4 3 5 0 0 3 4 1 1 100 100
Sample Output
YES
main.c
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