Given a sequence of integers and a positive integer , count the number of pairs that satisfy the following two conditions:
- , and
- .
Input Specification
The first line contains integer and , separated by a space.
The second line contains integers, which denotes .
In 50% of the test cases, .
Output Specification
The output contains an integer, which denotes the number of pairs that satisfies the two conditions. If the output is smaller than , please keep it as is. Otherwise, output the number mod .
Sample Input 1
5 6
1 2 3 4 5
Sample Output 1
6
Explanation for Sample Output 1
Among the pairs, , , , , , satisfy the conditions.
Sample Input 2
5 12
3 6 8 2 8
Sample Output 2
7
Explanation for Sample Output 2
, , , , , , satisfy the conditions.
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