Counting Haybales
Farmer John has just arranged his N haybales (1≤N≤100,000) at various points along the one-dimensional road running across his farm. To make sure they are spaced out appropriately, please help him answer Q queries (1≤Q≤100,000), each asking for the number of haybales within a specific interval along the road.
Problem credits: Nick Wu
Source: USA Computing Olympiad.
Input Format
The first line contains N and Q.
The next line contains N distinct integers, each in the range 0…1,000,000,000, indicating that there is a haybale at each of those locations.
Each of the next Q lines contains two integers A and B (0≤A≤B≤1,000,000,000) giving a query for the number of haybales between A and B, inclusive.
Output Format
You should write Q lines of output. For each query, output the number of haybales in its respective interval.