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Title: Geometric Sum

Problem statement
Given k, find the geometric sum i.e.
1 + 1/2 + 1/4 + 1/8 + ... + 1/(2^k)
Note: using recursion.

Detailed explanation ( Input/output format, Notes, Images )
Input format :
Integer k

Output format :
Geometric sum (upto 5 decimal places)

Constraints :
0  k;
    cout