Ton's work 1

var a,b:array of integer;
i,j,k,n,x,m,sa,sb,min:integer;
begin
  readln(n);
  min:=10000000000;
  for i:=1 to n do begin


  readln(x,m);
  if(m = 1) then begin
    setlength(a,length(a)+1);
    a[length(a)-1]:=x;
    sa+=x;
  end;
  if(m = 2) then begin
    setlength(b,length(b)+1);
    b[length(b)-1]:=x;
    sb+=x;
  end;
  end;
  for i:=0 to length(a)-1 do begin
    if (abs((sb+a[i])-(sa-a[i])) < min) then min:= abs((sb+a[i])-(sa-a[i]));
    end;
   for i:=0 to length(b)-1 do begin
    if (abs((sa+b[i])-(sb-b[i])) < min) then min:= abs((sa+b[i])-(sb-b[i]));
    end;
   if (abs(sa-sb)<min) then min:=abs(sa-sb);
   write(min);
end.