题目描述 This problem differs from one which was on the online contest. The sequence a1,a2,...,an a_{1},a_{2},...,a_{n} a 1 , a 2 , . . . , a n is called increasing, if ai<ai+1 a_{i}<a_{i+1} a i < a i + 1 for i<n i<n i < n . The sequence s1,s2,...,sk s_{1},s_{2},...,s_{k} s 1 , s 2 , . . . , s k is called the subsequence of the sequence a1,a2,...,an a_{1},a_{2},...,a_{n} a 1 , a 2 , . . . , a n , if there exist such a set of indexes 1<=i1<i2<...<ik<=n 1<=i_{1}<i_{2}<...<i_{k}<=n 1 < = i 1 < i 2 < . . . < i k < = n that aij=sj a_{ij}=s_{j} a i j = s j . In other