VCOWCAR - Xe ô tô của bò
Tác giả: RR
Ngôn ngữ: Pascal
{$R-,Q-}
//super fast algorithm invented by mr_invincible
const
FINP='';
FOUT='';
MAXN=50000;
var
n,l,m,d,kq:longint;
a:array[1..MAXN] of longint;
procedure inp; inline;
var
f:text;
i:longint;
begin
assign(f,FINP); reset(f);
read(f,n,m,d,l);
for i:=1 to n do read(f,a[i]);
close(f);
end;
procedure swap(var a,b:longint); inline;
var
temp:longint;
begin
temp:=a; a:=b; b:=temp;
end;
procedure sort(l,r:longint); inline;
var
i,j,mid:longint;
begin
i:=l; j:=r; mid:=a[l+random(r-l+1)];
repeat
while a[i]<mid do inc(i);
while a[j]>mid do dec(j);
if i<=j then
begin
swap(a[i],a[j]);
inc(i); dec(j);
end;
until i>j;
if i<r then sort(i,r);
if l<j then sort(l,j);
end;
procedure ans; inline;
var
f:text;
i:longint;
begin
assign(f,FOUT); rewrite(f);
kq:=0;
for i:=1 to n do
if a[i]-d*(kq div m)>=l then inc(kq);
writeln(f,kq);
close(f);
end;
begin
inp;
sort(1,n);
ans;
end.