weappadmin-api/app/Models/Guessing.php

<?php

namespace  App\Models;

use Illuminate\Database\Eloquent\Model;

class Guessing extends Model
{
    protected $table='guessing';

    public function get_user(){
        return $this->belongsTo(User::class,'user_id');
    }

    public function get_guessing(){
        return $this->hasMany(Guessing::class,'user_id','user_id');
    }

    public function get_challenge(){
        return $this->belongsTo(Challenge::class,'challenge_id');
    }

    public function get_challenge_challenge_user(){
        return $this->belongsToMany(User::class,'challenge','id','challenge_id','challenge_id','id')->withPivot('challenge_total','accept_total','challenge_day','challenge_success_id');
    }
    public function get_challenge_accept_user(){
        return $this->belongsToMany(User::class,'challenge','id','accept_id','challenge_id','id');
    }
}