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[Codeforces_gym_102136] I.Permutations again

传送门 Description Given a sequence \(A_i\) consisting of \(N\) integers. Find the number of pairs \((L, R)\) for which the subsegment \({A_L, A_{L + 1}, ...,A_R}\) is a permutation of \(R - L + 1\) numbers. A permutation of \(K\) numbers is a