#include <fstream>
using namespace std;
#define dim 500005
int v[dim], mat[dim];

int main()
{
	ifstream fin("divk.in");
	ofstream fout("divk.out");
	int n, k, a, b, i , j;
	
	fin>>n >>k >>a >>b;
	int contor=0;
	for(i=1;i<=n;++i)
	{
		fin>>v[i];
		mat[i]=(v[i]+mat[i-1])%k;
		//if(mat[i]==0 && i>=a && i<=b)
		//	++contor;
	}
	
	
	for(int d=a;d<=b;++d)
	{
		int x=0;
		for(j=d;j<=n;++j,++x)
			if( (mat[j]-mat[x])%k==0)
				++contor;
	}
	
	fout<<contor;
				
	
	return 0;
}