PKU3269 build a new barn

首先我们了解到本题在一维情况时就是著名的士兵排队。当然由于汉密尔顿距离的定义，我们依旧可以如法炮制！

         但是我通过无数次WA法相这道题里有一些细节值得考虑。首先，题目描述中没有是要求选择点不是提供的n个点之一，最开始看反了，囧了……其次，我们求出符合的点后发现会出现ans=0的情况。所以我们还要讨论求出的部分的边界上某个点的四周。    

 

 program Building_A_New_Barn;const deltax:array[1..4] of longint=(0,0,1,-1); deltay:array[1..4] of longint=(1,-1,0,0); inf=200000000;var x,y,dx,dy:array [0..10001] of longint; min,xa,xb,ya,yb,n,ans:longint;procedure init;var i:longint;begin readln(n); for i:=1 to n do readln(x[i],y[i]); dx:=x; dy:=y;end;procedure swap(var a,b:longint);var t:longint;begin t:=a; a:=b; b:=t;end;procedure qsortx(s,t:longint);var l,r,key:longint;begin l:=s; r:=t; key:=x[random(t-s+1)+s]; while l<=r do begin while x[l]<key do inc(l); while x[r]>key do dec(r); if l<=r then begin swap(x[l],x[r]); inc(l); dec(r); end; end; if s<r then qsortx(s,r); if l<t then qsortx(l,t);end;procedure qsorty(s,t:longint);var l,r,key:longint;begin l:=s; r:=t; key:=y[random(t-s+1)+s]; while l<=r do begin while y[l]<key do inc(l); while y[r]>key do dec(r); if l<=r then begin swap(y[l],y[r]); inc(l); dec(r); end; end; if s<r then qsorty(s,r); if l<t then qsorty(l,t);end;procedure calcx;begin if n and 1=1 then begin xa:=x[(n+1) shr 1]; xb:=xa; end else begin xa:=x[n shr 1]; xb:=x[n shr 1+1]; end;end;procedure calcy;begin if n and 1=1 then begin ya:=y[(n+1) shr 1]; yb:=ya; end else begin ya:=y[n shr 1]; yb:=y[n shr 1+1]; end;end;function check(i,j:longint):boolean;begin if (i>=xa) and (i<=xb) and (j>=ya) and (j<=yb) then exit(true); exit(false);end;function dist(i,x,y:longint):longint;begin exit(abs(dx[i]-x)+abs(dy[i]-y));end;procedure calcdist;var i:longint;begin min:=0; ans:=(yb-ya+1)*(xb-xa+1); for i:=1 to n do begin inc(min,dist(i,xa,ya)); if check(dx[i],dy[i]) then dec(ans); end;end;procedure special;var xt,yt,i,k,mint:longint;begin if ans<>0 then exit; ans:=0; min:=inf; for k:=1 to 4 do begin mint:=0; xt:=xa+deltax[k]; yt:=ya+deltay[k]; for i:=1 to n do inc(mint,dist(i,xt,yt)); if mint<min then begin ans:=1; min:=mint; end else if mint=min then inc(ans); end;end;procedure outit;begin writeln(min,' ',ans);end;begin assign(input,'a.in'); reset(input); assign(output,'a.out'); rewrite(output); init; qsortx(1,n); qsorty(1,n); calcx; calcy; calcdist; special; outit; close(input); close(output);end.