NITK06  MODIFY SEQUENCE
Suppose we have a sequence of nonnegative integers, Namely a_{1}, a_{2}, ..., a_{n}. At each time we can choose one term a_{i} with 0 < i < n and we subtract 1 from both a_{i} and a_{i+1}. We wonder whether we can get a sequence of all zeros after several operations.
Input
The first line is the number of test cases T (0 < T <= 20).
The first line of each test case is a number N (0 < N <= 10000). The next line is N nonnegative integers, 0 <= a_{i} <= 10^{9}.
Output
If it can be modified into all zeros with several operations output “YES” in a single line, otherwise output “NO” instead.
Example
Input: 2 2 1 2 2 2 2 Output: NO YES
Explanation
It is clear that [1 2] can be reduced to [0 1] but no further to convert all integers to 0. Hence, the output is NO.
In second case, output is YES as [2 2] can be reduced to [1 1] and then to [0 0] in just two steps.
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Vars:
20150807 05:40:23
easy one...need to observe pattern thats it :)


rk:
20150629 15:31:59
nice adhoc ques. 

:.Mohib.::
20150223 15:13:06
nice... 

Ankit Jain:
20131201 19:04:17
easy and nice..there should be more such probs on spoj.. 

Raushan Kumar:
20131104 15:21:22
good problem 
Added by:  Gaurav Jain 
Date:  20130925 
Time limit:  0.5s1s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: ASM64 