For a permutation π\pi of the integers from 11 to 1010, define S(π)=∑i=19(π(i)−π(i+1))⋅(4+π(i)+π(i+1)),S(\pi) = \sum_{i=1}^{9} (\pi(i) - \pi(i+1))\cdot (4 + \pi(i) + \pi(i+1)), where π(i)\pi (i) denotes the iith element of the permutation. Suppose that MM is the maximum possible value of S(π)S(\pi) over all permutations π\pi of the integers from 11 to 1010. Determine the number of permutations π\pi for which S(π)=MS(\pi) = M.

Source: 2012-2013 Winter Online Math Open

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