PROBLEM STATEMENT
One Saturday evening you are playing a game of online Scrabble. Your opponent is a very good 
player, but this time you managed to win. After a brief conversation, you are told: "I am clearly 
better than you, but one game is simply not enough to prove it." Your opponent then makess the 
following bet: "If we play 10 games, you will win less than 5 ... and this will happen every time, 
even if we try this 10 times in a row!". 

You will solve a more general problem using the following parameters: 
- an int  trials  denoting the number of meetings in which a set of games is played. 
- an int  games  denoting the number of games that are to be played in each meeting.
- an int  winsNeeded  denoting the number of victories you need in one of the meetings to win the 
bet. 
- an int  winChance  denoting the probability in percent of winning one particular game. 
Return a double between 0 and 1, denoting the probability you have to win the bet.



DEFINITION
Class:ScrabbleBet
Method:estimate
Parameters:int, int, int, int
Returns:double
Method signature:double estimate(int trials, int games, int winsNeeded, int winChance)


NOTES
-Your return value must have an absolute or relative error less than 1e-9.


CONSTRAINTS
- trials  will be between 1 and 50, inclusive.
- games  will be between 1 and 20, inclusive.
- winsNeeded will be between 1 and  games, inclusive.
- winChance  will be between 0 and 100, inclusive.


EXAMPLES

0)
2
2
1
50

Returns: 0.9375

There are 4 possible ways a meeting could evolve: 
 - you lose both games.
 - you lose game 1 and you win game 2.
 - you win game 1 and you lose game 2.
 - you win both games. 
Your opponent has a 1/4 chance of not losing the bet after the first meeting. Since there are two 
meetings, your opponent's chances to win the bet are 1/4 * 1/4 = 1/16. Thus, you have a 15/16 
chance to win the bet.


1)
2
2
2
50

Returns: 0.4375

This time your opponent has a 3/4 chance of not losing the bet after one meeting and a 9/16 chance 
of not losing the bet after the two meetings. Your chances are now 1 - 9/16 = 7/16.


2)
10
10
5
25

Returns: 0.5566860567603682

3)
2
20
5
10

Returns: 0.08448495352665641

4)
50
15
1
0

Returns: 0.0

5)
50
17
16
100

Returns: 1.0

6)
50
10
10
75

Returns: 0.9448701546682944

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