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#include<iostream>
using namespace std;
const int N = 500'010;
long long pref[N];
int n, k;
long long find_ans(int b)
{
int cnt[k] = {0};
long long ans = 0;
for(int i = 0; i <= b; ++i)
ans += cnt[pref[i]], cnt[pref[i]]++;
for(int i = b; i <= n; i ++)
cnt[pref[i-b]]-- , ans += cnt[pref[i]]++;
return ans;
}
int main()
{
int s, e;
cin >> n >> k >> s >> e;
for(int i = 1; i <= n; i ++)
cin >> pref[i];
pref[0] = 0;
for(int i = 0; i < n; i ++)
pref[i+1] += pref[i];
for(int i = 0; i <= n; i ++)
pref[i] %= k;
cout << find_ans(e+1) - find_ans(s) << endl;
return 0;
}