This is the source. I'd appreciate if you answered to swin@mail2000.ru
-----------------------
Program acm1203;
Var n          :longint;
    A          :array [1..30001] of integer;
    i,j,k,b,e  :longint;
Begin
  Readln(N);
  For i:=1 to 30001 do
  A[i]:=32000;

  k:=32000;
  For i:=1 to N do
  Begin
    Read(b,e);
    If b>e then
           Begin b:=b+e; e:=b-e; b:=b-e; End;{Dont tink this is
necessary}
    if b<k then k:=b;
    if e<A[b] then A[b]:=e;
  End;

  j:=0;
  While k<=30000 do
  Begin
    Inc(j);
    k:=A[k];
    repeat
      inc(k);
    Until (A[k]<>32000)or(k>30000)
  End;
  Writeln(j);
End.

'Cause you're loh!

Chadnov get your stupid mouth busy again. Suck it , retard.

Try this data:
5
1 1000
2 3
5 7
9 11
45 57