#include <bits/stdc++.h>

using namespace std;
int v[500005];
int main()
{
    freopen("divk.in","r",stdin);
    freopen("divk.out","w",stdout);
    int n,k,a,b,x,i,j,cnt=0;
    scanf("%d%d%d%d",&n,&k,&a,&b);
    for(i=1;i<=n;++i)
    {
        scanf("%d",&x);
        v[i]=(v[i-1]+x)%k;
    }
    for(i=a;i<=b;++i)
        if(v[i]==0)
            ++cnt;
    for(i=b;i<=n;++i)
        for(j=i-a+1;j>=i-b+1;--j)
            if(v[i]==v[j])
                ++cnt;
    printf("%d",cnt);
    return 0;
}