FREQUENT - Frequent values


You are given a sequence of n integers a1, a2 ... an in non-decreasing order. In addition to that, you are given several queries consisting of indices i and j (1 ≤ i ≤ j ≤ n). For each query, determine the most frequent value among the integers ai ... aj.

Input Specification

The input consists of several test cases. Each test case starts with a line containing two integers n and q (1 ≤ n, q ≤ 100000). The next line contains n integers a1 ... an (-100000 ≤ ai ≤ 100000, for each i ∈ {1 ... n}) separated by spaces. You can assume that for each i ∈ {1 ... n-1}: ai ≤ ai+1. The following q lines contain one query each, consisting of two integers i and j (1 ≤ i ≤ j ≤ n), which indicate the boundary indices for the query.

The last test case is followed by a line containing a single 0.

Output Specification

For each query, print one line with one integer: The number of occurrences of the most frequent value within the given range.

Sample Input

10 3
-1 -1 1 1 1 1 3 10 10 10
2 3
1 10
5 10
0

Sample Output

1
4
3

A naive algorithm may not run in time!

hide comments
joydip007x: 2019-06-09 14:27:42

*Segment tree size [ 4*N]
*1 base indexing

hungbmt1503: 2019-06-04 05:10:04

oh, forgot that this problem has multiple test case :"))

Last edit: 2019-06-04 05:10:48
eagleshadow: 2019-05-29 10:37:18

Nice problem!!
Try GSS1 first, if you get stuck

xxfalconxx: 2019-05-29 08:44:43

Read the question carefully, it has multiple test cases and last test case ends with 0, Wasted so much time because of this :/

krishna Murari: 2019-02-07 13:04:08

handling the 0 case cost half my day

nour_massri: 2019-01-27 20:51:09

same as Uva 11235 :)

joe85123: 2018-11-28 16:47:03

solving GSS1 first really helped a lot!

DOT: 2018-08-01 20:12:41

Phew! At last, AC. Didn't understand multiple test cases will come until 0 is entered.
@thekidnamedme, same for me. 125th answer there is different from my solution.

horizon121: 2018-06-10 08:11:29

AC in one Go .
Solved GSS1 before.

thekidnamedme: 2018-06-07 13:13:09

Interesting find. My AC solution differs from that on spoj toolkit for testcase #23 (1 conflict).
http://spojtoolkit.com/history/FREQUENT


Added by:Adrian Kuegel
Date:2007-07-06
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ERL JS-RHINO NODEJS PERL6 VB.NET
Resource:University of Ulm Local Contest 2007