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Link: https://uva.onlinejudge.org/external/108/10883.pdf
I could figure out that let's say for 5 numbers the answer is (Arr[1] + 4 * Arr[2] + 6 * Arr[3] + 4 * Arr[4] + Arr[5])/2^16. So the problem basically reduces to finding the values in the nth row of pascal's triangle and power of 2. But I am not very sure as to how to implement the solution. Any help is really appreciated.
HINT: If you calculate in the paper, you will see answer is
You can use the fact that
, i.e. no need of pre-computation. You can find a similar problem here
Yeah, recursively like C(n, k) = C(n, k - 1) * (n - k - 1) / k
HINT 2: Number of combinations can calculated recursively: C(n, k) = C(n, k - 1) * (n - k - 1) / k
Also C(n, 0) = 1
HINT 3: For bigger n finding combination will not be work, so use logarithm : )
If you couldn't solve, see solution with logarithm and numerical combinations