CF766B.Mahmoud and a Triangle

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题目描述

Mahmoud has nn line segments, the ii -th of them has length aia_{i} . Ehab challenged him to use exactly 33 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 33 of them to form a non-degenerate triangle.

Mahmoud should use exactly 33 line segments, he can't concatenate two line segments or change any length. A non-degenerate triangle is a triangle with positive area.

输入格式

The first line contains single integer nn ( 3<=n<=1053<=n<=10^{5} ) — the number of line segments Mahmoud has.

The second line contains nn integers a1,a2,...,ana_{1},a_{2},...,a_{n} ( 1<=ai<=1091<=a_{i}<=10^{9} ) — the lengths of line segments Mahmoud has.

输出格式

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.

输入输出样例

  • 输入#1

    5
    1 5 3 2 4
    

    输出#1

    YES
    
  • 输入#2

    3
    4 1 2
    

    输出#2

    NO
    

说明/提示

For the first example, he can use line segments with lengths 22 , 44 and 55 to form a non-degenerate triangle.

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