CF976C Nested Segments

You are given a sequence $ a_{1},a_{2},...,a_{n} $ of one-dimensional segments numbered $ 1 $ through $ n $ . Your task is to find two distinct indices $ i $ and $ j $ such that segment $ a_{i} $ lies within segment $ a_{j} $ . Segment $ [l_{1},r_{1}] $ lies within segment $ [l_{2},r_{2}] $ iff $ l_{1}>=l_{2} $ and $ r_{1}

The first line contains one integer $ n $ ( $ 1

Print two distinct indices $ i $ and $ j $ such that segment $ a_{i} $ lies within segment $ a_{j} $ . If there are multiple answers, print any of them. If no answer exists, print -1 -1.

In the first example the following pairs are considered correct: - $ (2,1),(3,1),(4,1),(5,1) $ — not even touching borders; - $ (3,2),(4,2),(3,5),(4,5) $ — touch one border; - $ (5,2),(2,5) $ — match exactly.