P3382: [Usaco2004 Open]cave cows 3 The three cows in the cave

First, let's make sure that the longest Manhattan distance is only possible for x1+y2-(X2+y2) and x1-y1-(x2-y2) so we only need to maintain four values,

Represents Max (X+y), respectively; Max (x-y); Min (x+y); Min (x-y);

So the answer is Max (max (x+y)-min (x+y), Max (x-y)-min (x-y).

1 Constmaxn=3000000;2 varMaxadd,minadd,maxdec,mindec,i,a,b,n:longint;3 function Max (a,b:longint): Longint;4 begin5   ifA>B then exit (a)6     Elseexit (b);7 end;8 function min (a,b:longint): Longint;9 beginTen   ifa<B then exit (a) One     Elseexit (b); A end; - begin -MINADD:=MAXN; mindec:=MAXN; the READLN (n); -    fori:=1to n Do - begin - Readln (A, b); +Maxadd:=max (maxadd,a+b); -Minadd:=min (minadd,a+b); +Maxdec:=max (maxdec,a-b); AMindec:=min (mindec,a-b); at end; -Writeln (Max (maxadd-minadd,maxdec-mindec)); -End.

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P3382: [Usaco2004 Open]cave cows 3 The three cows in the cave