题目描述
You've got an array, consisting of n integers a1,a2,...,an. Also, you've got m queries, the i-th query is described by two integers li,ri. Numbers li,ri define a subsegment of the original array, that is, the sequence of numbers a[li],a[li+1],a[li+2],...,a[ri]. For each query you should check whether the corresponding segment is a special subarray.
A special subarray is a sequence of integers b1,b2,...,bk, such that it first decreases, it doesn't increase. In other words, there is such integer x (1=x ≤ k), that the following inequation fulfills: b1=b2=...=bx=bx+1=bx+2...=bk. Note that the non-increasing and the non-decreasing sequences are also considered special subarray.
Example
4 3 2 1
1 2 3 4
9 6 5 3 1
Above all are special
But
8 7 5 9
3 6 8 7 9
These are not special because it increases after decreasing
Input:
The first line contains two integers n and m (1=n,m=10^5) — the number of array elements and the number of queries. The second line contains the sequence of integers a1,a2,...,an (1=a[i]=10^9), where number a[i] stands for the i-th array element.
The following m lines contain the description of the queries. The i-th line contains the description of the i-th query, consisting of two integers li, ri (1=li=ri=n) — the boundaries of the subsegment of the initial array.
The numbers in the lines are separated by single spaces.
NOTE: Consider array indexing starts from 1
Output:
Print m lines, in the i-th line print word "Yes" (without the quotes), if the subsegment that corresponds to the i-th query is the special subarray, or word "No" (without the quotes) otherwise.
SAMPLE INPUT
8 6
1 2 1 3 3 5 2 1
1 3
2 3
2 4
8 8
1 4
5 8
SAMPLE OUTPUT
Yes
Yes
No
Yes
No
Yes
输入格式
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输出格式
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