NITK06 - MODIFY SEQUENCE
Suppose we have a sequence of non-negative integers, Namely a1, a2, ..., an. At each time we can choose one term ai with 0 < i < n and we subtract 1 from both ai and ai+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 non-negative integers, 0 <= ai <= 109.
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.
hide comments
Vars:
2015-08-07 05:40:23
easy one...need to observe pattern thats it :)
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rk:
2015-06-29 15:31:59
nice adhoc ques. |
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:.Mohib.::
2015-02-23 15:13:06
nice... |
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Ankit Jain:
2013-12-01 19:04:17
easy and nice..there should be more such probs on spoj.. |
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Raushan Kumar:
2013-11-04 15:21:22
good problem |
Added by: | Gaurav Jain |
Date: | 2013-09-25 |
Time limit: | 0.5s-1s |
Source limit: | 50000B |
Memory limit: | 1536MB |
Cluster: | Cube (Intel G860) |
Languages: | All except: ASM64 |