rt
贡献一次WA
附代码（Pascal）
var
  p,i,x,y,zero:longint;
  f,before,count:array [0..30010] of longint;
  ch:char;

function find(x:longint):longint;
begin
  if f[x]=x then exit(x);
  find:=find(f[x]);
  inc(before[x],before[f[x]]);
  f[x]:=find;
end;

procedure merge(x,y:longint);
begin
  x:=find(x); y:=find(y);
  if x=y then exit;
  f[x]:=y;
  inc(before[x],count[y]);
  inc(count[y],count[x]);
end;

begin
  readln(p);
  for i:=1 to 30000 do begin count[i]:=1; f[i]:=i; end;
  for i:=1 to p do
    begin
      read(ch);
      if ch='M' then
        begin
          readln(x,y);
          merge(x,y);
        end
      else
        begin
          readln(x);
          zero:=find(x);
          writeln(before[x]);
        end;
    end;
end.

• Re:保险起见，在输出前要路径压缩一次 (16) xc19881023 2016-05-03 14:18:33