Get Discount Pairs

Count the index pairs i<j such that prices[i]+prices[j] is divisible by x. Items have their own identities, so repeated prices can form several pairs, and an item cannot be paired with itself.

输入格式

The first line contains n x and the second line contains n prices. The original bounds are 1≤n≤100000, 1≤x≤2×10^9, prices[i]≥1. Only the superscript 9 of the original upper bound on prices survives and its base is missing, so this site explicitly adds price≤10^9 and does not claim this restores the original upper bound.

输出格式

Output a single integer, the answer.

样例 1

输入：

5 60
31 25 85 29 35

输出：

3

样例 2

输入：

3 2
1 1 1

输出：

3

样例 3

输入：

1 1
1

输出：

0

样例说明

The outputs of the three public examples are 3; 3; and 0, checked by independent enumeration or direct simulation.