#include <bits/stdc++.h>
using namespace std;

ifstream fin("divk.in");
ofstream fout("divk.out");

/**
f(x)= nr de secv de lungime <= x si care sunt divizibile cu k

Sol = f(B) - f(A-1)
*/

int n, k, A, B;
int a[500005], sp[500005];

long long F(int x)
{
    int fr[100001] = {0}, i, j;
    long long cnt = 0;
    sp[0] = j = 0;
    fr[0] = 1;
    for(i = 1; i <= n; i++)
    {
        sp[i] = (sp[i - 1] + a[i]) % k;
        if(i - j > x)
        {
            fr[sp[j]]--;
            j++;
        }
        cnt += fr[sp[i]];
        fr[sp[i]]++;
    }
    return cnt;
}

int main()
{
    fin >> n >> k >> A >> B;
    for(int i = 1; i <= n; i++)
        fin>>a[i];
    fout << F(B) - F(A - 1);
    return 0;
}