CF1851A.Escalator Conversations

传统题 时间 2000 ms 内存 256 MiB 3 尝试 1 已通过 1 标签

Escalator Conversations

One day, Vlad became curious about who he can have a conversation with on the escalator in the subway. There are a total of nn passengers. The escalator has a total of mm steps, all steps indexed from 11 to mm and ii-th step has height iki \cdot k.

Vlad's height is HH centimeters. Two people with heights aa and bb can have a conversation on the escalator if they are standing on different steps and the height difference between them is equal to the height difference between the steps.

For example, if two people have heights 170170 and 180180 centimeters, and m=10,k=5m = 10, k = 5, then they can stand on steps numbered 77 and 55, where the height difference between the steps is equal to the height difference between the two people: k2=52=10=180170k \cdot 2 = 5 \cdot 2 = 10 = 180 - 170. There are other possible ways.

Given an array hh of size nn, where hih_i represents the height of the ii-th person. Vlad is interested in how many people he can have a conversation with on the escalator individually.

For example, if n=5,m=3,k=3,H=11n = 5, m = 3, k = 3, H = 11, and h=[5,4,14,18,2]h = [5, 4, 14, 18, 2], Vlad can have a conversation with the person with height 55 (Vlad will stand on step 11, and the other person will stand on step 33) and with the person with height 1414 (for example, Vlad can stand on step 33, and the other person will stand on step 22). Vlad cannot have a conversation with the person with height 22 because even if they stand on the extreme steps of the escalator, the height difference between them will be 66, while their height difference is 99. Vlad cannot have a conversation with the rest of the people on the escalator, so the answer for this example is 22.

Input

The first line contains a single integer tt (1t10001 \le t \le 1000) — the number of test cases.

Then the descriptions of the test cases follow.

The first line of each test case contains integers: n,m,k,Hn, m, k, H (1n,m501 \le n,m \le 50, 1k,H1061 \le k,H \le 10^6). Here, nn is the number of people, mm is the number of steps, kk is the height difference between neighboring steps, and HH is Vlad's height.

The second line contains nn integers: h1,h2,,hnh_1, h_2, \ldots, h_n (1hi1061 \le h_i \le 10^6). Here, hih_i represents the height of the ii-th person.

Output

For each test case, output a single integer — the number of people Vlad can have a conversation with on the escalator individually.

Note

The first example is explained in the problem statement.

In the second example, Vlad can have a conversation with the person with height 1111.

In the third example, Vlad can have a conversation with people with heights: 44,74,98,6244, 74, 98, 62. Therefore, the answer is 44.

In the fourth example, Vlad can have a conversation with the person with height 7373.

Samples

7
5 3 3 11
5 4 14 18 2
2 9 5 6
11 9
10 50 3 11
43 44 74 98 62 60 99 4 11 73
4 8 8 49
68 58 82 73
7 1 4 66
18 66 39 83 48 99 79
9 1 1 13
26 23 84 6 60 87 40 41 25
6 13 3 28
30 70 85 13 1 55
2
1
4
1
0
0
3

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