Time Limit: 10 minutes

Check whether array A is a permutation.

A non-empty array A consisting of N integers is given. A permutation is a sequence containing each element from 1 to N once, and only once.

]]>Time Limit: 10 minutes

Check whether array A is a permutation.

A non-empty array A consisting of N integers is given. A permutation is a sequence containing each element from 1 to N once, and only once.

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