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
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

nuhash_40: 2018-05-18 18:06:37

Thought my submission would give tle as i used map in query
but AC in one go :D

hackerwizard: 2018-04-13 21:48:46

AC in one go!!!

gyanendra371: 2018-03-23 14:12:24

someone pls explain the code on codechef link
https://discuss.codechef.com/questions/124793/help-in-understanding-segment-tree-merge-function-of-spoj-frequent-question

coolio_1: 2018-03-04 07:53:43

There are multiple test cases! Cost me one WA! :( Btw segment tree rocks! :D

abhishek18620: 2017-08-04 01:09:25

AC in one go.... ;)

aman2309: 2017-07-20 05:07:35

Dont miss taking test cases... costed me a wrong submission

praney_rai: 2017-06-20 12:30:56

getting tle with mo's any comments (anyone who did it with mo's) ?

dhrv_shrma04: 2017-06-18 18:54:01

Very good question
Try GSS1 first


Added by:Adrian Kuegel
Date:2007-07-06
Time limit:0.936s
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