#include <bits/stdc++.h>
using namespace std;
//#define int long long
int k[40] = {0,0,990,1010,1970,2030,2940,3060,3930,4060,4970,5030,5990,6010,7000};
int f[40];
int a,b,n;
int ans = 0;
void AAA(int x)
{
	for(int i=1;i<=n;i++)
	{
		if(!f[i]&&k[i]>=k[x]+a&&k[i]<=k[x]+b)
		{
			if(f[i]==7000)
			{
				ans++;
				return;
			}
			f[i] = true;
			AAA(i);
			f[i] = false;
		}
		else if(k[x]+a>=7000)
		{
			ans++;
			return; 
		}
	}
}
signed main()
{
//	freopen(".in","r",stdin);
//	freopen(".out","w",stdout);
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin>>a>>b>>n;
	n += 14;
	for(int i=15;i<=n;i++) cin>>k[i];
	AAA(1);
	cout<<ans;
	return 0;
}