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CF2008A.Sakurako's Exam
Sakurako's Exam
Today, Sakurako has a math exam. The teacher gave the array, consisting of ones and twos.
In an array, Sakurako must place either a '+' or a '-' in front of each element so that the sum of all elements in the array equals .
Sakurako is not sure if it is possible to solve this problem, so determine whether there is a way to assign signs such that the sum of all elements in the array equals .
Input
The first line contains a single integer () — the number of test cases.
The only line of each test case contains two integers and () — the number of '1's and the number of '2's in the array.
Output
For each test case, output "Yes" if you can make the sum of the entire array equal to , and "No" otherwise.
You can output each letter in any case (lowercase or uppercase). For example, the strings "yEs", "yes", "Yes", and "YES" will be accepted as a positive answer.
Note
- , : This means the array is — it is impossible to add the signs '
+' or '-' to get as a result; - , : This means the array is — it is impossible to add the signs '
+' or '-' to get as a result; - , : This means the array is — it is possible to add the signs '
+' or '-' to get as a result (); - , : This means the array is — it is possible to add the signs '
+' or '-' to get as a result ();
Samples
5
0 1
0 3
2 0
2 3
3 1
NO
NO
YES
YES
NO
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