Arithmetic Sequence

Time Limit
2s
Memory Limit
65536KB
Judge Program
Standard
Ratio(Solve/Submit)
100.00%(1/1)
Description:

A sequence b1,b2,⋯,bn are called (d1,d2)-arithmetic sequence if and only if there exist i(1≤i≤n) such that for every j(1≤j<i),bj+1=bj+d1 and for every j(i≤j<n),bj+1=bj+d2.
Teacher Mai has a sequence a1,a2,⋯,an. He wants to know how many intervals [l,r](1≤l≤r≤n) there are that al,al+1,⋯,ar are (d1,d2)-arithmetic sequence.

Input:

There are multiple test cases.

For each test case, the first line contains three numbers n,d1,d2(1≤n≤105,|d1|,|d2|≤1000), the next line contains n integers a1,a2,⋯,an(|ai|≤109).

Output:

For each test case, print the answer.

Sample Input:
5 2 -2
0 2 0 -2 0
5 2 3
2 3 3 3 3
Sample Output:
12
5
Source:

2015 Multi-University Training Contest 9


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