CF1951A.Dual Trigger

传统题 时间 2000 ms 内存 256 MiB 4 尝试 1 已通过 1 标签

Dual Trigger

Ngọt - LẦN CUỐI (đi bên em xót xa người ơi)

There are nn lamps numbered 11 to nn lined up in a row, initially turned off. You can perform the following operation any number of times (possibly zero):

  • Choose two non-adjacent{}^\dagger lamps that are currently turned off, then turn them on.

Determine whether you can reach configuration ss, where si=1s_i = 1 means the ii-th lamp is turned on, and si=0s_i = 0 otherwise.

{}^\dagger Only lamp ii and i+1i + 1 are adjacent for all 1i<n1 \le i \lt n. Note that lamp nn and 11 are not adjacent when n2n \ne 2.

Input

Each test contains multiple test cases. The first line contains an integer tt (1t10001 \le t \le 1000) — the number of test cases. The description of the test cases follows.

The first line of each test case contains an integer nn (1n501 \le n \le 50) — the number of lamps.

The second line of each test case contains a binary string ss of size nn — the final desired configuration.

Output

For each test case, print on one line "YES" if we can reach the configuration ss via applying the given operation any number of times. Otherwise, print "NO".

Note

In the first test case, the sequence of operation could have been as follows (note that initially ss is all zero): 0000000000} \to \mathtt{\color{red}{1}0000000\color{red}{1}0} \to \mathtt{1\color{red}{1}00000\color{red}{1}10} \to \mathtt{110\color{red}{1}0\color{red}{1}0110.

In the third test case, we don't have to do any operation.

In the fourth test case, we cannot do any operation, but we need the first lamp to be on. Therefore, it is impossible to achieve the desired state.

Samples

5
10
1101010110
10
1001001110
6
000000
1
1
12
111111111111
YES
NO
YES
NO
YES

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