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Time Limit: 1 s Memory Limit: 512 MB Total points: 100
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# 8534. Merging Cells

统计

Note: The memory limit for this problem is 512MB, twice the default.

Bessie is having fun playing a famous online game, where there are a bunch of cells of different labels and sizes. Cells get eaten by other cells until only one winner remains.

There are N (2N5000) cells in a row labeled 1N from left to right, with initial sizes s1,s2,,sN (1si105). While there is more than one cell, a pair of adjacent cells is selected uniformly at random and merged into a single new cell according to the following rule:

If a cell with label a and current size ca is merged with a cell with label b and current size cb, the resulting cell has size ca+cb and label equal to that of the larger cell, breaking ties by larger label. Formally, the label of the resulting cell is {aca>cbbca<cbmax

For each label i in the range 1\dots N, the probability that the final cell has label i can be expressed in the form \frac{a_i}{b_i} where b_i\not\equiv 0\pmod{10^9+7}. Output a_ib_i^{-1}\pmod{10^9+7}.

Input

The first line contains N.

The next line contains s_1,s_2,\dots, s_N.

Output

The probability of the final cell having label i modulo 10^9+7 for each i in 1\dots N on separate lines.

Examples

Input 1

3
1 1 1

Output 1

0
500000004
500000004

There are two possibilities, where (a,b)\to c means that the cells with labels a and b merge into a new cell with label c.

(1, 2) -> 2, (2, 3) -> 2
(2, 3) -> 3, (1, 3) -> 3

So with probability 1/2 the final cell has label 2 or 3.

Input 2

4
3 1 1 1

Output 2

666666672
0
166666668
166666668

The six possibilities are as follows:

(1, 2) -> 1, (1, 3) -> 1, (1, 4) -> 1
(1, 2) -> 1, (3, 4) -> 4, (1, 4) -> 1
(2, 3) -> 3, (1, 3) -> 1, (1, 4) -> 1
(2, 3) -> 3, (3, 4) -> 3, (1, 3) -> 3
(3, 4) -> 4, (2, 4) -> 4, (1, 4) -> 4
(3, 4) -> 4, (1, 2) -> 1, (1, 4) -> 1

So with probability 2/3 the final cell has label 1, and with probability 1/6 the final cell has label 3 or 4.

Scoring

  • Input 3: N\le 8
  • Inputs 4-8: N\le 100
  • Inputs 9-14: N\le 500
  • Inputs 15-22: No additional constraints.

Problem credits: Benjamin Qi