There is a stack of water glasses in a form of pascal triangle and a person wants to pour the water at the topmost glass, but the capacity of each glass is 1 unit. Overflow takes place in such a way that after 1 unit, 1/2 of remaining unit gets into bottom left glass and other half in bottom right glass.Now John pours K units of water in the topmost glass and wants to know how much water is there in the Cth glass of the Rth row.
Note: Assume that there are enough glasses in the triangle till no glass overflows.

Example 1:
Input:
K = 3, R = 2, C = 1
Output:
1.000000
Explanation:
After the first glass, 2 units of water
will remain and they will spread equally
on the two glasses on the second row.
Therefore, the glass on the 2nd row and
1st column will have 1 unit of water.
Example 2:
Input:
K = 3, R = 2, C = 2
Output:
1.000000
Explanation:
After the first glass, 2 units of water
will remain and they will spread equally
on the two glasses on the second row.
Therefore, the glass on the 2nd row and
2nd column will have 1 unit of water.

Your Task:
You don't need to read input or print anything. Your task is to complete the function waterOverflow() which takes 3 Integers K, R and C as input and returns the amount of water(6 digits of precision) in the Cth glass of Rth row.

Expected Time Complexity: O(K^{2})
Expected Auxiliary Space: O(K^{2})

Constraints:
1 <= K <= 500
1 <= R,C <= K

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