program tiaoyuan;
var
n,v0,i,j,biaozhi:integer;
t:real;
a:array[1..100,1..2]of real;
bc,jilu:array[1..100]of integer;
begin
assign (input,'jump.in');
reset (input);
assign (output,'jump.out');
rewrite (output);
readln (n,v0);
for i:=1 to n do
read (bc[i]);
a[1,1]:=0;
a[1,2]:=sqrt(3)*(bc[1]/2);
for i:=2 to n do
begin
a[i,1]:=a[i-1,1]+(bc[i-1]+bc[i])/2;
a[i,2]:=sqrt(3)*(bc[i]/2)
end;
for i:=1 to n-1 do
begin
for j:=i+1 to n do
begin
t:=(a[j,1]-a[i,1])/v0;
if (a[i,2]+v0*t-5*t*t)>=a[j,2] then
jilu[i]:=j
else
break
end
end;
for i:=1 to n-1 do
if jilu[i]>0 then
write (jilu[i],' ');
close (input);
close (output)
end.