Given a set of sticks of various lengths, is it possible to join them end-to-end to form a square?
The first line of input contains N , the number of test cases. Each test case begins with an integer 4 ≤ M ≤ 20, the number of sticks. M integers follow; each gives the length of a stick — an integer between 1 and 10,000.
For each case, output a line containing ‘yes’ if is is possible to form a square; otherwise output ‘no’.
範例輸入 1
3 4 1 1 1 1 5 10 20 30 40 50 8 1 7 2 6 4 4 3 5
範例輸出 1
yes no yes
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