how can create update function in AuthController in Laravel

I am using Laravel 5.2 and created make:auth command to generate register and login forms. now I need create user data edit form and routes it. this is create function of AuthController

 protected function create(array $data)
    {
        return User::create([
            'username' => $data['username'],
            'email' => $data['email'],
            'password' => bcrypt($data['password']),
        ]);
    }

and this is edit.blade.php file

@extends('layouts.app')

@section('content')
<div class="container">
    <div class="row">
        <div class="col-md-8 col-md-offset-2">
            <div class="panel panel-default">
                <div class="panel-heading">User Profile</div>
                @include('layouts.partials.alerts')
                <div class="panel-body">
                    <form class="form-horizontal" role="form" method="POST" action="">
                        

                        <div class="form-group">
                            <label for="username" class="col-md-4 control-label">Name</label>

                            <div class="col-md-6">
                                <input id="username" type="text" class="form-control" name="username" value="">

                                @if ($errors->has('username'))
                                    <span class="help-block">
                                        <strong></strong>
                                    </span>
                                @endif
                            </div>
                        </div>

                        <div class="form-group">
                            <label for="email" class="col-md-4 control-label">E-Mail Address</label>

                            <div class="col-md-6">
                                <input id="email" type="email" class="form-control" name="email" value="">

                                @if ($errors->has('email'))
                                    <span class="help-block">
                                        <strong></strong>
                                    </span>
                                @endif
                            </div>
                        </div>

                        <div class="form-group">
                            <label for="password" class="col-md-4 control-label">Password</label>

                            <div class="col-md-6">
                                <input id="password" type="password" class="form-control" name="password" value="">

                                @if ($errors->has('password'))
                                    <span class="help-block">
                                        <strong></strong>
                                    </span>
                                @endif
                            </div>
                        </div>

                        ">
                            <label for="password-confirm" class="col-md-4 control-label">Confirm Password</label>

                            <div class="col-md-6">
                                <input id="password-confirm" type="password" class="form-control" name="password_confirmation">

                                @if ($errors->has('password_confirmation'))
                                    <span class="help-block">
                                        <strong></strong>
                                    </span>
                                @endif
                            </div>
                        </div> --}}

                        <div class="form-group">
                            <div class="col-md-6 col-md-offset-4">
                                <button type="submit" class="btn btn-primary">
                                    <i class="fa fa-btn fa-user"></i> Update
                                </button>
                            </div>
                        </div>
                    </form>
                </div>
            </div>
        </div>
    </div>
</div>
@endsection

how can I create update function to username,email and password fields and route it?

via Chebli Mohamed