program ppg;
var x,y:array[0..100]of longint;
    f:array[0..100,0..100]of longint;
    t,k,m,n,i,j,max:longint;
function min(a,b:longint):longint;
begin
if a>b then min:=b else min:=a;
end;
begin
assign(input,'ppg.in');
reset(input);
assign(output,'ppg.out');
rewrite(output);
readln(n);
for t:=1 to n do
 readln(x[t],y[t]);
for t:=1 to n-1 do
  for k:=t+1  to n do
    begin
      f[t,k]:=(abs(x[t]-x[k])+abs(y[t]-y[k])+1)div 2;
      f[k,t]:=f[t,k];
    end;
for i:=1 to n do
  for t:=1 to n do
    for k:=1 to n do
      if (t<>i)and(t<>k)and(i<>k)and(f[t,i]+f[i,k]<f[t,k]) then
        f[t,k]:=f[t,i]+f[i,k];
for t:=1 to n do
  for k:=1 to n do
    if t<>k then
      if max<f[t,k] then
        max:=f[t,k];
writeln(max);
close(output);
end.