Slice.py

def solution(A):
    min_avg_value = (A[0] + A[1]) / 2.0  # The mininal average
    min_avg_pos = 0  # The begin position of the first
    # slice with mininal average

    for index in range(0, len(A) - 2):
        # Try the next 2-element slice
        if (A[index] + A[index + 1]) / 2.0 < min_avg_value:
            min_avg_value = (A[index] + A[index + 1]) / 2.0
            min_avg_pos = index
        # Try the next 3-element slice
        if (A[index] + A[index + 1] + A[index + 2]) / 3.0 < min_avg_value:
            min_avg_value = (A[index] + A[index + 1] + A[index + 2]) / 3.0
            min_avg_pos = index

    # Try the last 2-element slice
    if (A[-1] + A[-2]) / 2.0 < min_avg_value:
        min_avg_value = (A[-1] + A[-2]) / 2.0
        min_avg_pos = len(A) - 2

    return min_avg_pos

print (solution([9,1,2,1,1]))

#A non-empty array A consisting of N integers is given. A pair of integers (P, Q), such that 0 ≤ P < Q < N,
# is called a slice of array A (notice that the slice contains at least two elements).
# The average of a slice (P, Q) is the sum of A[P] + A[P + 1] + ... + A[Q] divided by the length of the slice.
# To be precise, the average equals (A[P] + A[P + 1] + ... + A[Q]) / (Q − P + 1).