Program CODEVS1380;

type arr=record

        u,v,next:longint;

    end;

const maxn=;

var eg:array[..maxn] of arr;

    last:array[..maxn] of longint;

    a:array[..maxn] of longint;

    f:array[..maxn,..] of longint;

    fa:array[..maxn] of longint;

    i,n,u,v,j,root:longint;

procedure add(u,v:longint);

begin

  inc(j);

  eg[j].u:=u;

  eg[j].v:=v;

  eg[j].next:=last[u];

  last[u]:=j;

end;

function max(a,b:longint):longint;

begin

  if a>b then exit(a) else exit(b);

end;

procedure dfs(u:longint);

var i,v,sum1,sum2:longint;

begin

  if last[u]=- then

    begin

      f[u,]:=;

      f[u,]:=a[u];

      exit;

    end;

  i:=last[u]; sum1:=; sum2:=;

  while i<>- do

    begin

      v:=eg[i].v;

      dfs(v);

      sum1:=sum1+f[v,];

      sum2:=sum2+max(f[v,],f[v,]);

      i:=eg[i].next;

    end;

  f[u,]:=sum2;

  f[u,]:=sum1+a[u];

end;

begin

  readln(n);

  j:=-;

  for i:= to maxn do last[i]:=-;

  for i:= to n do readln(a[i]);

  readln(v,u);

  while (v<>) and (u<>) do

    begin

      fa[v]:=u;

      add(u,v);

      readln(v,u);

    end;

  for i:= to n do if fa[i]= then root:=i;

  dfs(root);

  writeln(max(f[root,],f[root,]));

end.