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CF1436A.Reorder
Reorder
For a given array consisting of integers and a given integer find if it is possible to reorder elements of the array in such a way that equals ? It is forbidden to delete elements as well as insert new elements. Please note that no rounding occurs during division, for example, .
Input
The first line contains a single integer — the number of test cases (). The test cases follow, each in two lines.
The first line of a test case contains two integers and (, ). The second line contains integers () — the elements of the array.
Output
For each test case print "YES", if it is possible to reorder the elements of the array in such a way that the given formula gives the given value, and "NO" otherwise.
Note
In the first test case one of the reorders could be . The sum is equal to $(\frac{1}{1} + \frac{2}{2} + \frac{5}{3}) + (\frac{2}{2} + \frac{5}{3}) + (\frac{5}{3}) = 8$. The brackets denote the inner sum , while the summation of brackets corresponds to the sum over .
Samples
2
3 8
2 5 1
4 4
0 1 2 3
YES
NO
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