Tinkoff Internship Warmup Round 2018 and Codeforces Round 475 (Div. 1)
E
Circles of Waiting
Codeforces
3100
原题
← D→
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A chip was placed on a field with coordinate system onto point $(0, 0)$.

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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.

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Find out the expected time after which chip will move away from origin at a distance greater than $*R*$ (i.e. image will be satisfied).

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Input

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First line contains five integers $*R*, *a*_{1}, *a*_{2}, *a*_{3}$ and $*a*_{4}$ ($0 ≤ *R* ≤ 50, 1 ≤ *a*_{1}, *a*_{2}, *a*_{3}, *a*_{4} ≤ 1000$).

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Probabilities $*p*_{*i*}$ can be calculated using formula image.

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Output

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It can be shown that answer for this problem is always a rational number of form image, where image.

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Print $*P*·*Q*^{ - 1}$ modulo $10^{9} + 7$.

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Note

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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 $1$.

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Answers to the second and the third tests: image and image.

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样例

Input #1
0 1 1 1 1
Output #1
1
InputCopy OutputCopy
Input #2
1 1 1 1 1
Output #2
666666674
InputCopy OutputCopy
Input #3
1 1 2 1 2
Output #3
538461545
InputCopy OutputCopy
题目信息
题号
963E
时间限制
2 s
内存限制
256 MB
标签
数学

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