Time Limit: 2.5 seconds
Memory Limit: 512 megabytes
Once, Leha found in the left pocket an array consisting of n integers, and in the right pocket q queries of the form l r k. If there are queries, then they must be answered. Answer for the query is minimal x such that x occurs in the interval l r strictly more than times or - 1 if there is no such number. Help Leha with such a difficult task.
First line of input data contains two integers n and q (1 ≤ n, q ≤ 3·105) — number of elements in the array and number of queries respectively.
Next line contains n integers a1, a2, ..., an (1 ≤ ai ≤ n) — Leha's array.
Each of next q lines contains three integers l, r and k (1 ≤ l ≤ r ≤ n, 2 ≤ k ≤ 5) — description of the queries.