#include <stdio.h>
long m=0,n=0,u=0,l=0,y[1048576];
unsigned long long int p=0;
void cit()
{
long i,buf,lt=-1,nr=-1;
FILE *f;
f=fopen("secv5.in","r");
fscanf(f,"%d %d %d",&n,&u,&l);

for(i=0;i<n;i++)
{
fscanf(f,"%d",&buf);
if(buf==lt)y[nr]++;
if(buf!=lt){nr++;y[nr]++;lt=buf;}
}
m=nr+1;
fclose(f);
}

void rez()
{
long i,j,l1=m-u+1,l2=0;


for(i=0;i<l1;i++)
{
l2=i+l;
for(j=i+u-1;((j<l2)&&(j<m));j++)
p+=y[i]*y[j];
}

}

void scr()
{
FILE *f;
f=fopen("secv5.out","w");
fprintf(f,"%d\n","p");
fclose(f);
}

int main()
{
cit();
rez();
scr();
return 0;
}