合并果子问题浅析

const maxn=10000;
       max=2*maxn-1;
type
      node=record
         data:int64;
         prt,lch,rch:0..max;
        end;
     treetype=array[1..max]of node;
var tree:treetype;n,i:longint;s:int64;
procedure hufm(var tree:treetype);
var k,i,j:longint; 
 function min(h:integer):integer;
  var i,p:longint;m1:int64;
  begin
    m1:=9223372036854775807;
    for p:=1 to h do
     if (tree[p].prt=0)and(m1>tree[p].data) then
      begin
        i:=p;m1:=tree[p].data;
      end;
    min:=i;
  end;
begin
 fillchar(tree,sizeof(tree),0);
 for i:=1 to n do read(tree[i].data);
 for k:=n+1 to 2*n-1 do
  begin
    i:=min(k-1);tree[i].prt:=k;tree[k].lch:=i;
    j:=min(k-1);tree[j].prt:=k;tree[k].rch:=j;
    tree[k].data:=tree[i].data+tree[j].data;
  end;
end;
begin
  readln(n);
  hufm(tree);
  for i:=n+1 to 2*n-1 do
   s:=s+tree[i].data;
  writeln(s);
end.

var n,i,x,y,s:longint;
    a:array[1..10000]of longint;
procedure swap(var a,b:longint);
var t:longint;
begin
  t:=a;
  a:=b;
  b:=t;
end;
function min(n:longint):longint;
var i,p,q:longint;
begin
  p:=maxlongint;
  for i:=1 to n do
   if a[i]<p then
   begin
    p:=a[i];
    q:=i;
   end;
  min:=q;
end;
begin
  s:=0;
  readln(n);
  for i:=1 to n do
   read(a[i]);
  while n>1 do
  begin
   x:=min(n);swap(a[n],a[x]);dec(n);
   y:=min(n);a[y]:=a[y]+a[n+1];
   s:=s+a[y];
  end;
  writeln(s);
end.

var a,b:array[1..10002]of longint;
    x,y,y1,n,i,s:longint;
procedure sort(l,r: longint);
var
i,j,x,y: longint;
begin
   i:=l;
   j:=r;
   x:=a[(l+r) div 2];
   repeat
      while a[i]<x do
        inc(i);
      while x<a[j] do
        dec(j);
      if not(i>j) then
         begin
            y:=a[i];a[i]:=a[j];a[j]:=y;
            inc(i);j:=j-1;
         end;
   until i>j;
   if l<j then
     sort(l,j);
   if i<r then
     sort(i,r);
end;
begin
    readln(n);
    s:=0;
    for i:=1 to 10002 do
     begin
      a[i]:=maxlongint;
      b[i]:=maxlongint;
     end;
    for i:=1 to n do
     read(a[i]);
    sort(1,n);
    x:=1;y:=1;y1:=1;
    while y1<n do
         if (a[x+1]<=b[y]) then begin b[y1]:=a[x]+a[x+1];inc(x,2); inc(y1);end
      else if a[x]>=b[y+1] then
        begin
         b[y1]:=b[y]+b[y+1];
         inc(y1);inc(y,2);
        end
       else
        begin
         b[y1]:=b[y]+a[x];
         inc(x);inc(y);inc(y1);
        end; 

    for i:=1 to n-1 do s:=s+b[i];
    writeln(s);
end.