CF598C Nearest vectors

You are given the set of vectors on the plane, each of them starting at the origin. Your task is to find a pair of vectors with the minimal non-oriented angle between them. Non-oriented angle is non-negative value, minimal between clockwise and counterclockwise direction angles. Non-oriented angle is always between $ 0 $ and $ π $ . For example, opposite directions vectors have angle equals to $ π $ .

First line of the input contains a single integer $ n $ ( $ 2

Print two integer numbers $ a $ and $ b $ ( $ a≠b $ ) — a pair of indices of vectors with the minimal non-oriented angle. You can print the numbers in any order. If there are many possible answers, print any.