1 #pragma GCC optimize("Ofast")
2 #include <bits/stdc++.h>
3 #define maxn 13003
4 #define _for(i,a,b) for(int i = (a);i < b;i ++)
5 typedef long long ll;
6 using namespace std;
7
8 inline ll read()
9 {
10 ll ans = 0;
11 char ch = getchar(), last = ' ';
12 while(!isdigit(ch)) last = ch, ch = getchar();
13 while(isdigit(ch)) ans = (ans << 1) + (ans << 3) + ch - '0', ch = getchar();
14 if(last == '-') ans = -ans;
15 return ans;
16 }
17 inline void write(ll x)
18 {
19 if(x < 0) x = -x, putchar('-');
20 if(x >= 10) write(x / 10);
21 putchar(x % 10 + '0');
22 }
23 int L,S,T,M;
24 int stone[103];
25 int bridge[103];
26 int dp[11004];
27 int stone2[11004];
28 int main()
29 {
30 L = read(); S = read(); T = read(); M = read();
31 _for(i,1,M+1)
32 stone[i] = read();
33
34 sort(stone+1,stone+1+M);
35 if(S==T)
36 {
37 int rnt = 0;
38 _for(i,1,M+1)
39 if(stone[i]%T==0)
40 rnt ++;
41 write(rnt);
42 return 0;
43 }
44
45 _for(i,1,M+1)
46 {
47 int d = stone[i]-stone[i-1];
48 if(d>=100) d = 100;
49 bridge[i] = bridge[i-1]+d;
50 stone2[bridge[i]] = 1;
51 }
52 L = bridge[M] + 100;
53
54 memset(dp,0x7f,sizeof(dp));
55 dp[0] = 0;
56
57 _for(i,1,L+1)
58 _for(j,S,T+1)
59 if(i - j >= 0)
60 if(stone2[i])
61 dp[i] = min(dp[i],dp[i-j]+1);
62 else
63 dp[i] = min(dp[i],dp[i-j]);
64
65 int rnt = INT_MAX;
66 _for(i,bridge[M],L+1)
67 rnt = min(rnt,dp[i]);
68
69 write(rnt);
70 return 0;
71 }
