#arc102d. [arc102_d]Revenge of BBuBBBlesort!

[arc102_d]Revenge of BBuBBBlesort!

Problem Statement

You are given a permutation of 1,2,...,N1,2,...,N: p1,p2,...,pNp_1,p_2,...,p_N. Determine if the state where pi=ip_i=i for every ii can be reached by performing the following operation any number of times:

  • Choose three elements pi1,pi,pi+1p_{i-1},p_{i},p_{i+1} (2leqileqN12\\leq i\\leq N-1) such that pi1>pi>pi+1p_{i-1}>p_{i}>p_{i+1} and reverse the order of these three.

Constraints

  • 3leqNleq3×1053 \\leq N \\leq 3 × 10^5
  • p1,p2,...,pNp_1,p_2,...,p_N is a permutation of 1,2,...,N1,2,...,N.

Input

Input is given from Standard Input in the following format:

NN p1p_1 :: pNp_N

Output

If the state where pi=ip_i=i for every ii can be reached by performing the operation, print Yes; otherwise, print No.


Sample Input 1

5
5
2
1
4
3

Sample Output 1

Yes

The state where pi=ip_i=i for every ii can be reached as follows:

  • Reverse the order of p1,p2,p3p_1,p_2,p_3. The sequence pp becomes 1,2,5,4,31,2,5,4,3.
  • Reverse the order of p3,p4,p5p_3,p_4,p_5. The sequence pp becomes 1,2,3,4,51,2,3,4,5.

Sample Input 2

4
3
2
4
1

Sample Output 2

No

Sample Input 3

7
3
2
1
6
5
4
7

Sample Output 3

Yes

Sample Input 4

6
5
3
4
1
2
6

Sample Output 4

No