Little Elephant and Permutations

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The Little Elephant likes permutations. This time he has a permutation A[1], A[2], ..., A[N] of numbers 1, 2, ..., N. He calls a permutation A good, if the number of its inversions is equal to the number of its local inversions. The number of inversions is equal to the number of pairs of integers (i; j) such that 1 ≤ i j ≤ N and A[i] > A[j], and the number of local inversions is the number of int

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solution.cppC++17

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