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**
     * Update the specified resource in storage.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return \Illuminate\Http\Response
     */
    public function asignar(Request $request) 
    {

      $valor = $request->valor;//donde obtiene el dato "daniela"
      $consulta=usuarios::where('user_id',$valor)->get();

        foreach ($consulta as $value) {

        $userad = usuarios::findOrFail($value->user_id);//limite de un registro
        $userad->asignacion = 'jhonier';
        $userad->save();
    }

           return redirect()->route('cuenta.tareas')->with('success','Registro actualizado satisfactoriamente');

    }

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