You're going to generate an array $$$a$$$ with a length of at most $$$n$$$, where each $$$a_{i}$$$ equals either $$$1$$$ or $$$-1$$$.
You generate this array in the following way.
After the array is generated, you calculate $$$s_{i} = a_{1} + a_{2} + a_{3}+ \ldots + a_{i}$$$. Specially, $$$s_{0} = 0$$$. Then you let $$$S$$$ equal to $$$\displaystyle \max_{i=0}^{k}{s_{i}}$$$. That is, $$$S$$$ is the maximum prefix sum of the array $$$a$$$.
You are given $$$n+1$$$ integers $$$h_{0} , h_{1}, \ldots ,h_{n}$$$. The score of an array $$$a$$$ with maximum prefix sum $$$S$$$ is $$$h_{S}$$$. Now, for each $$$k$$$, you want to know the expected score for an array of length $$$k$$$ modulo $$$10^9+7$$$.
Each test contains multiple test cases. The first line contains a single integer $$$t$$$ ($$$1 \le t \le 5000$$$) — the number of test cases. Their description follows.
The first line contains an integer $$$n$$$ ($$$1\le n \le 5000$$$).
Then for the following $$$n$$$ lines, each line contains two integers $$$x_{i}$$$ and $$$y_{i}$$$ ($$$0 \le x_{i} < 10^9 + 7$$$, $$$1\le y_{i} < 10^9 + 7$$$, $$$x_{i} \le y_{i}$$$), indicating $$$p_{i} = \frac{x_{i}}{y_{i}}$$$.
The next line contains $$$n+1$$$ integers $$$h_{0},h_{1}, \ldots, h_{n}$$$ ($$$0 \le h_{i} < 10^9 + 7$$$).
It is guaranteed that the sum of $$$n$$$ over all test cases does not exceed $$$5000$$$.
For each test case, output $$$n$$$ integers in one single line, the $$$i$$$-th of which denotes the expected score for an array of length $$$i$$$, modulo $$$10^9 + 7$$$.
Formally, let $$$M = 10^9 + 7$$$. It can be shown that the answer can be expressed as an irreducible fraction $$$\frac{p}{q}$$$, where $$$p$$$ and $$$q$$$ are integers and $$$q \not \equiv 0 \pmod{M}$$$. Output the integer equal to $$$p \cdot q^{-1} \bmod M$$$. In other words, output such an integer $$$x$$$ that $$$0 \le x < M$$$ and $$$x \cdot q \equiv p \pmod{M}$$$.
421 21 21 2 331 31 45 51 1 1 132 54 60 24 3 2 155 65 71 61 34 79 0 4 5 2 4
500000005 750000007 1 1 1 200000005 333333339 333333339 500000005 880952391 801587311 781746041 789304620
In the first test case, if we choose $$$k=1$$$, there are $$$2$$$ possible arrays with equal probabilities: $$$[1]$$$ and $$$[-1]$$$. The $$$S$$$ values for them are $$$1$$$ and $$$0$$$. So the expected score is $$$\frac{1}{2}h_{0} + \frac{1}{2}h_{1} = \frac{3}{2}$$$. If we choose $$$k=2$$$, there are $$$4$$$ possible arrays with equal probabilities: $$$[1,1]$$$, $$$[1,-1]$$$, $$$[-1,1]$$$, $$$[-1,-1]$$$, and the $$$S$$$ values for them are $$$2,1,0,0$$$. So the expected score is $$$\frac{1}{2}h_{0} + \frac{1}{4}h_{1} + \frac{1}{4}h_{2} = \frac{7}{4}$$$.
In the second test case, no matter what the $$$S$$$ value is, the score is always $$$1$$$, so the expected score is always $$$1$$$.
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