Codeforces Round 114 (Div. 1)
B
Wizards and Huge Prize
Codeforces
1800
原题
← AC →
翻译中…

One must train much to do well on wizardry contests. So, there are numerous wizardry schools and magic fees.

翻译中…

One of such magic schools consists of $*n*$ tours. A winner of each tour gets a huge prize. The school is organised quite far away, so one will have to take all the prizes home in one go. And the bags that you've brought with you have space for no more than $*k*$ huge prizes.

翻译中…

Besides the fact that you want to take all the prizes home, you also want to perform well. You will consider your performance good if you win at least $*l*$ tours.

翻译中…

In fact, years of organizing contests proved to the organizers that transporting huge prizes is an issue for the participants. Alas, no one has ever invented a spell that would shrink the prizes... So, here's the solution: for some tours the winner gets a bag instead of a huge prize. Each bag is characterized by number $*a*_{*i*}$ — the number of huge prizes that will fit into it.

翻译中…

You already know the subject of all tours, so you can estimate the probability $*p*_{*i*}$ of winning the $*i*$-th tour. You cannot skip the tour under any circumstances.

翻译中…

Find the probability that you will perform well on the contest and will be able to take all won prizes home (that is, that you will be able to fit all the huge prizes that you won into the bags that you either won or brought from home).

翻译中…

Input

翻译中…

The first line contains three integers $*n*$, $*l*$, $*k*$ ($1 ≤ *n* ≤ 200, 0 ≤ *l*, *k* ≤ 200$) — the number of tours, the minimum number of tours to win, and the number of prizes that you can fit in the bags brought from home, correspondingly.

翻译中…

The second line contains $*n*$ space-separated integers, $*p*_{*i*}$ ($0 ≤ *p*_{*i*} ≤ 100$) — the probability to win the $*i*$-th tour, in percents.

翻译中…

The third line contains $*n*$ space-separated integers, $*a*_{*i*}$ ($1 ≤ *a*_{*i*} ≤ 200$) — the capacity of the bag that will be awarded to you for winning the $*i*$-th tour, or else -1, if the prize for the $*i*$-th tour is a huge prize and not a bag.

翻译中…

Output

翻译中…

Print a single real number — the answer to the problem. The answer will be accepted if the absolute or relative error does not exceed $10^{ - 6}$.

翻译中…

Note

翻译中…

In the first sample we need either win no tour or win the third one. If we win nothing we wouldn't perform well. So, we must to win the third tour. Other conditions will be satisfied in this case. Probability of wining the third tour is 0.3.

翻译中…

In the second sample we win the only tour with probability 1.0, and go back home with bag for it.

翻译中…

样例

Input #1
3 1 0
10 20 30
-1 -1 2
Output #1
0.300000000000
InputCopy OutputCopy
Input #2
1 1 1
100
123
Output #2
1.000000000000
InputCopy OutputCopy
题目信息
题号
167B
时间限制
2 s
内存限制
256 MB
标签
动态规划
数学
概率论

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