A chip was placed on a field with coordinate system onto point $(0, 0)$.
Every second the chip moves randomly. If the chip is currently at a point $(*x*, *y*)$, after a second it moves to the point $(*x* - 1, *y*)$ with probability $*p*_{1}$, to the point $(*x*, *y* - 1)$ with probability $*p*_{2}$, to the point $(*x* + 1, *y*)$ with probability $*p*_{3}$ and to the point $(*x*, *y* + 1)$ with probability $*p*_{4}$. It's guaranteed that $*p*_{1} + *p*_{2} + *p*_{3} + *p*_{4} = 1$. The moves are independent.
Find out the expected time after which chip will move away from origin at a distance greater than $*R*$ (i.e.
will be satisfied).
Input
First line contains five integers $*R*, *a*_{1}, *a*_{2}, *a*_{3}$ and $*a*_{4}$ ($0 ≤ *R* ≤ 50, 1 ≤ *a*_{1}, *a*_{2}, *a*_{3}, *a*_{4} ≤ 1000$).
Probabilities $*p*_{*i*}$ can be calculated using formula
.
Output
It can be shown that answer for this problem is always a rational number of form
, where
.
Print $*P*·*Q*^{ - 1}$ modulo $10^{9} + 7$.
Note
In the first example initially the chip is located at a distance $0$ from origin. In one second chip will move to distance $1$ is some direction, so distance to origin will become $1$.
Answers to the second and the third tests:
and
.
样例
0 1 1 1 1
1
1 1 1 1 1
666666674
1 1 2 1 2
538461545
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