CF849A Odds and Ends

Description

Where do odds begin, and where do they end? Where does hope emerge, and will they ever break? Given an integer sequence $ a_{1},a_{2},...,a_{n} $ of length $ n $ . Decide whether it is possible to divide it into an odd number of non-empty subsegments, the each of which has an odd length and begins and ends with odd numbers. A subsegment is a contiguous slice of the whole sequence. For example, $ {3,4,5} $ and $ {1} $ are subsegments of sequence $ {1,2,3,4,5,6} $ , while $ {1,2,4} $ and $ {7} $ are not.

Input Format

The first line of input contains a non-negative integer $ n $ ( $ 1

Output Format

Output "Yes" if it's possible to fulfill the requirements, and "No" otherwise. You can output each letter in any case (upper or lower).

Explanation/Hint

In the first example, divide the sequence into $ 1 $ subsegment: $ {1,3,5} $ and the requirements will be met. In the second example, divide the sequence into $ 3 $ subsegments: $ {1,0,1} $ , $ {5} $ , $ {1} $ . In the third example, one of the subsegments must start with $ 4 $ which is an even number, thus the requirements cannot be met. In the fourth example, the sequence can be divided into $ 2 $ subsegments: $ {3,9,9} $ , $ {3} $ , but this is not a valid solution because $ 2 $ is an even number.