#include<stdio.h>
#include<string.h>
FILE *f,*g;
int n,l,u,nr;
int ise[200],ife[200],le;
int sol1[200],sol2[200],ls;

char sir[200][10];





int main()
{
f=fopen("secv5.in","r");
g=fopen("secv5.out","w");
fscanf(f,"%d %d %d\n",&n,&l,&u);
int i,k,j,p;
fscanf(f,"%s",&sir[1]);
for(i=2;i<=n;i++)
{
fscanf(f,"%s",&sir[i]);
for(j=1;j<i;j++)
if(strcmp(sir[j],sir[i])==0)
  {

   le++;
   ise[le]=j;
   ife[le]=i;
 }
}


ls++;
sol1[ls]=1;
sol2[ls]=l;
for(i=1;i<=n-l;i++)
  for(j=i+l-1;j<=i+u-1;j++)
    if(i!=1 && j!=l)
   {

   for(k=1;k<=ls;k++)
    {

      int ok=1;
      for(p=1;p<=le;p++)
      {
      if((ise[p]>=sol1[k] && ise[p]<=sol2[k]) && (ife[p]>=sol1[k] && ife[p]<=sol2[k])&& (ise[p]>=i && ise[p]<=j) && (ife[p]>=i && ife[p]<=j)) ok=0;
      }
      if (ok)
      {
      ls++;
      sol1[ls]=i;
      sol2[ls]=j;
      }

      }
    }

fprintf(g,"%d",ls);
return 0;
}