Given N numbers [N<=10^5], count the total pairs of numbers that have a difference of K where [K>0 and K<1e9]. Each of the N numbers will be greater than 0 and be at least K away from 2^31-1 (Everything can be done with 32 bit integers).
Input Format:
1st line contains N & K (integers). 2nd line contains N numbers of the set. All the N numbers are assumed to be distinct.
Output Format:
One integer saying the number of pairs of numbers that have a diff K.
Sample Input #00:
5 2
1 5 3 4 2
Sample Output #00:
3
Sample Input #01:
10 1
363374326 364147530 61825163 1073065718 1281246024 1399469912 428047635 491595254 879792181 1069262793
Sample Output #01:
0