Mahmoud and a Triangle

# 题目大意： 给出n个数，若其中3个数能形成一个非退化的三角形则输出‘YES’，否则输出‘NO’（没有引号） # 输入格式： 第一行包含单个整数n（3<=n<=10^5）表示有n条边可供选择 第二行有n个a1,a2,a3...an（1<=ai<=10^9）表示每条边的长度 # 输出格式： 一行，如果符合，则输出‘YES’，否则输出‘NO’（没有引号）

Mahmoud has $ n $ line segments, the $ i $ -th of them has length $ a_{i} $ . Ehab challenged him to use exactly $ 3 $ line segments to form a non-degenerate triangle. Mahmoud doesn't accept challenges unless he is sure he can win, so he asked you to tell him if he should accept the challenge. Given the lengths of the line segments, check if he can choose exactly $ 3 $ of them to form a non-degenerate triangle. Mahmoud should use exactly $ 3 $ line segments, he can't concatenate two line segments or change any length. A non-degenerate triangle is a triangle with positive area.

The first line contains single integer $ n $ ( $ 3<=n<=10^{5} $ ) — the number of line segments Mahmoud has. The second line contains $ n $ integers $ a_{1},a_{2},...,a_{n} $ ( $ 1<=a_{i}<=10^{9} $ ) — the lengths of line segments Mahmoud has.

In the only line print "YES" if he can choose exactly three line segments and form a non-degenerate triangle with them, and "NO" otherwise.

5
1 5 3 2 4

YES

3
4 1 2

NO

For the first example, he can use line segments with lengths $ 2 $ , $ 4 $ and $ 5 $ to form a non-degenerate triangle.