bzoj1487

还是仙人掌，和1023一样的考虑方法
比1023简单但比1040难
环形dp的处理方法和1040一样

type node=record
       po,next:longint;
     end;

var f:array[0..100010,0..1] of longint;
    e:array[0..400010] of node;
    a,p,fa,dfn,low:array[0..100010] of longint;
    h,p0,p1,q0,q1,i,x,y,n,m,len:longint;

function max(a,b:longint):longint;
  begin
    if a>b then exit(a) else exit(b);
  end;

function min(a,b:longint):longint;
  begin
    if a>b then exit(b) else exit(a);
  end;

procedure add(x,y:longint);
  begin
    inc(len);
    e[len].po:=y;
    e[len].next:=p[x];
    p[x]:=len;
  end;

procedure work(x,y:longint);
  var p,q:longint;
  begin
    q:=y;
    while fa[q]<>x do
    begin
      p:=fa[q];
      p0:=f[p,0]+max(q0,q1);
      p1:=f[p,1]+q0;
      q0:=p0;
      q1:=p1;
      q:=p;
    end;
    p0:=max(q0,q1);
    p1:=q0;
  end;

procedure dp(x,y:longint);
  begin
    q0:=f[y,0];
    q1:=f[y,1];
    work(x,y);
    f[x,0]:=f[x,0]+p0;
    q0:=f[y,0];
    q1:=-2147483647;
    work(x,y);
    f[x,1]:=f[x,1]+p1;
  end;

procedure tarjan(x:longint);
  var i,y:longint;
  begin
    inc(h);
    dfn[x]:=h;
    low[x]:=h;
    i:=p[x];
    f[x,0]:=0;
    f[x,1]:=a[x];
    while i<>0 do
    begin
      y:=e[i].po;
      if fa[x]<>y then
      begin
        if dfn[y]=0 then
        begin
          fa[y]:=x;
          tarjan(y);
        end;
        low[x]:=min(low[x],low[y]);
        if dfn[x]<low[y] then
        begin
          f[x,0]:=f[x,0]+max(f[y,0],f[y,1]);
          f[x,1]:=f[x,1]+f[y,0];
        end;
      end;
      i:=e[i].next;
    end;
    i:=p[x];
    while i<>0 do
    begin
      y:=e[i].po;
      if (fa[y]<>x) and (dfn[y]>dfn[x]) then
        dp(x,y);
      i:=e[i].next;
    end;
  end;

begin
  readln(n,m);
  for i:=1 to m do
  begin
    readln(x,y);
    add(x,y);
    add(y,x);
  end;
  for i:=1 to n do
    read(a[i]);
  tarjan(1);
 // writeln(f[3,1],' ',f[3,0]);
  writeln(max(f[1,1],f[1,0]));
end.