var a,b,o:array[0..10000]of longint;

i,j,max,n,x,y:longint;

procedure sqrt(l,r:longint);

var i,j,t,s:longint;

begin

i:=l;j:=r; s:=a[(l+r) div 2];

repeat

while a[i]<s do inc(i);

while a[j]>s do dec(j);

if i<=j then begin

t:=a[i]; a[i]:=a[j]; a[j]:=t;

t:=b[i]; b[i]:=b[j]; b[j]:=t;

inc(i);dec(j);

end;

until i>j;

if l<j then sqrt(l,j);

if i<r then sqrt(i,r);

end;

begin

readln(x,y);

while true do

begin

fillchar(o,sizeof(o),0);

if (x=0)and(y=0) then halt;

readln(n);

for i:=1 to n do readln(a[i],b[i]);

sqrt(1,n);

readln(x,y);

b[0]:=-maxlongint;

for i:=1 to n do

for j:=0 to i-1 do

if (b[j]<b[i])and(o[j]+1>o[i]) then o[i]:=o[j]+1;

max:=-maxlongint;

for i:=1 to n do

if o[i]>max then max:=o[i];

writeln(max);

end;

end.