Easy Queries

You are given an array A consisting of N positive integers. You have to answer Q queries on it of following type: - l r k : Let S denote the sorted (in increasing order) set of elements of array A with its indices between l and r. Note that set S contains distinct elements (i.e. no duplicates). You need to find kth number in it. If such a number does not exist, i.e. the S has less than k element