pairs

Accepts: 133
Submissions: 715
Time Limit: 2000/1000 MS (Java/Others)
Memory Limit: 32768/32768 K (Java/Others)
Problem Description
John has $n$ points on the X axis, and their coordinates are $(x[i],0),(i=0,1,2,бн,n-1)$. He wants to know how many pairs$$ that $|x[b]-x[a]| \leq k. (a
Input
The first line contains a single integer $T$ (about 5), indicating the number of cases. Each test case begins with two integers $n,k (1 \leq n \leq 100000,1 \leq k \leq {10}^{9})$. Next $n$ lines contain an integer $x[i] ({-10}^{9} \leq x[i] \leq {10}^{9})$, means the X coordinates.
Output
For each case, output an integer means how many pairs$$ that $|x[b]-x[a]| \leq k$.
Sample Input
2
5 5
-100
0
100
101
102
5 300
-100
0
100
101
102
Sample Output
3
10