program Project1;

type pe=0..1;

var l,i,j,s,t,k,f,m:integer;

a:array[0..10000]of integer;

b:array[0..10000]of pe;

begin

readln(l);

readln(s,t,m);

for i:=1 to l do

begin

b[i]:=0;

a[i]:=maxint;

end;

for i:=1 to m do

begin

read(j);b[j]:=1;

end;

for i:=s to t do a[i]:=b[i];

f:=s;

for i:=1 to l div s do

begin

for j:=f to f+t-s do

for k:=s to t do

if (j+k