https://community.topcoder.com/stat?c=problem_statement&pm=13268&rd=16187
Problem Summary : Given an array of 1<=N<=47 integers. All the integers are in range [1,47]. Given two number low,high(1<=low<=high<=47). We have pick a sub sequence of the given array in minimum move that contains only the numbers in range [low,high] and all the numbers in range[low,high]. In a single move we can pick a continuous sequence of numbers from the given array. We to find number of ways to pick such sub sequence in minimum move.
Examples 0)

{2, 1, 3} 1 3 Returns: 1 The only way to choose the subset is to choose all animals. 1)

{3, 4, 1, 3, 4, 2} 1 3 Returns: 2 In the optimal solution we send away animals #2, #3, and #5 (0-based indices). Animals #2 and #3 form one group, animal #5 forms the other. 2)

{3, 4, 3, 1, 6, 2, 5, 7, 5, 2} 2 6 Returns: 2 3)

{3, 1, 4} 2 4 Returns: -1 4)

{2, 1, 3, 1, 4} 1 4 Returns: 1 Note that we are not required to minimize the number of animals we send. Here, we could select just four of these five animals but that would create two groups. A better solution is to select all five animals, then they all form a single group. 5)

{7, 12, 2, 12, 10, 13, 6, 5, 3, 3, 4, 11, 12, 4, 3, 1, 8, 11, 4, 7, 6, 5, 47} 2 7 Returns: 3 Don't figure out the DP idea. Can anyone show me a direction in the problem? Thanks in advance.