COI '12 #3 Snjeguljica
View as PDFIn a small village beyond seven hills and seven seas, Snow White lives together with  dwarves who
spend all their time eating and playing League of Legends. Snow White wants to put an end to this, so
she has organized gym classes for them.
At the beginning of each class, the dwarves must stand in line, ordered by their height. For the
purposes of this task, assume that the dwarves have heights  (each exactly once). However,
the dwarves' intelligence has somewhat deteriorated from the unhealthy lifestyle, so they are incapable
of ordering themselves by height. That's why Snow White helps them by issuing commands of the
form:
1 X Y-- dwarves at positionsand
in the line must switch places.
She also checks their ordering by issuing queries of the form:
2 A B-- do dwarves with heights(not necessarily in that order) occupy a contiguous subsequence of the current line?
Help the doofus dwarves follow Snow White's instructions and respond to her queries.
Input Specification
The first line of input contains the two positive integers  and 
, the number of dwarves and the
number of Snow White's requests, respectively 
.
The following line contains  space-separated positive integers from 
 to 
, each exactly once,
representing the initial arrangement of the dwarves.
Each of the following  lines contains a single Snow White's request, of the form 
1 X Y
 or 
2 A B , as described in the problem statement.
Output Specification
The output must contain one line for each request of type 2, containing the reply to the query, either
YES or NO.
Scoring
In test data worth a total of  points, for all requests of type 
, the constraint 
 holds.
Sample Input 1
5 3
2 4 1 3 5
2 2 5
1 3 1
2 2 5
Sample Output 1
NO
YES
Sample Input 2
7 7
4 7 3 5 1 2 6
2 1 7
1 3 7
2 4 6
2 4 7
2 1 4
1 1 4
2 1 4
Sample Output 2
YES
NO
YES
NO
YES
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