using namespace std;

#include <cstdio>
#include <cstring>
#include <iostream>

int N, K, A, B, v[1<<19], S[1<<19], re[1<<17];

long long rec( int len )
{
    memset( re, 0, sizeof( re ) );    
    
    long long ret = 0;
    
    if( !len )
        return ret;
    
    for( int i = 1; i <= len; i++ )
         re[ S[i] ]++,
         ret += (long long)(re[ S[i] ]); 
     
    for( int i = len + 1; i <= N; i++ )
         re[ S[i] ]++, re[ S[i - len] ]--,
         ret += (long long)(re[ S[i] ]);
    
    cout << len << " : " << ret << endl;
    
    return ret;
}

int main()
{
    freopen("divk.in", "r", stdin);
    freopen("divk.out", "w", stdout);
    
    int i;
    
    scanf("%d %d %d %d", &N, &K, &A, &B);
    for(i = 1; i <= N; i++)
        scanf("%d", v+i ),
        S[i] = S[i-1] + v[i],
        S[i] %= K;
    
    long long ret = rec( B ) - rec( A - 1 );
    
    cout << ret << endl;
    
    return 0;   
}