var n,m,k,i,j,h:longint;
    a:array[1..1000000] of longint;
    f,g:text;
procedure sterg(i,j:longint);
 var k,l:longint;
 begin
  l:=0;
  for k:=1 to n do
   if (k<i)or(k>j) then begin
    inc(l);
    a[l]:=a[k];
    end;
  n:=l;
  end;
begin
 assign(f,'stergeri.in');
 reset(f);
 read(f,n);
 read(f,m);
 readln(f,k);
 for i:=1 to n do
  a[i]:=i;
 for h:=1 to m do begin
  read(f,i);
  readln(f,j);
  sterg(i,j);
  end;
 close(f);
 assign(g,'stergeri.out');
 rewrite(g);
 writeln(g,a[k]);
 close(g);
end.