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An algorithm problem, please give me some advice

WBOYOriginal: 2016-08-18 09:15:281016browse

As shown in the picture above, there is a room. The time of entering the room is a record, and the time of leaving is a record. Each user's record is different. How to make the user's time period in the room into the following array form, which is stored in the database? The record is like this
['id'=>1,'uid'=>22,'stauts'=>'leave','time'=>1415947332]
['id'=>2, 'uid'=>22,'stauts'=>'Enter','time'=>1415947333]
['id'=>3,'uid'=>22,'stauts'=> 'Leave','time'=>1415997332]
['id'=>4,'uid'=>22,'stauts'=>'Enter','time'=>1416947333]
[ 'id'=>6,'uid'=>23,'stauts'=>'leave','time'=>1415947332]
['id'=>7,'uid'=> 23,'stauts'=>'Enter','time'=>1415947333]
['id'=>8,'uid'=>23,'stauts'=>'Leave','time '=>1415997332]
['id'=>9,'uid'=>23,'stauts'=>'Enter','time'=>1416947333]
...

<code>$data=[
    [0]=>[
        'begin_time'=>第一个进入时间,
        'end_time'=>第一个出去时间,
    ],
    [1]=>[
        'begin_time'=>第二个进入时间,
        'end_time'=>第二个出去时间,
    ],
    [2]=>[
        'begin_time'=>第三个进入时间,
        'end_time'=>第三个进出去时间,
    ],
    [3]=>[
        'begin_time'=>第四个进入时间,
        'end_time'=>第四个进出去时间,
    ]

.....
</code>

]

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An algorithm problem, please give me some advice

<code>$data=[
    [0]=>[
        'begin_time'=>第一个进入时间,
        'end_time'=>第一个出去时间,
    ],
    [1]=>[
        'begin_time'=>第二个进入时间,
        'end_time'=>第二个出去时间,
    ],
    [2]=>[
        'begin_time'=>第三个进入时间,
        'end_time'=>第三个进出去时间,
    ],
    [3]=>[
        'begin_time'=>第四个进入时间,
        'end_time'=>第四个进出去时间,
    ]

.....
</code>

]

<code><?php
$data = [];
$status = ['离开'=>'end_time','进入'=>'begin_time'];
$results = [
['id'=>1,'uid'=>22,'status'=>'离开','time'=>1415947332],
['id'=>2,'uid'=>22,'status'=>'进入','time'=>1415947333],
['id'=>3,'uid'=>22,'status'=>'离开','time'=>1415997332],
['id'=>4,'uid'=>22,'status'=>'进入','time'=>1416947333],
['id'=>6,'uid'=>23,'status'=>'离开','time'=>1415947332],
['id'=>7,'uid'=>23,'status'=>'进入','time'=>1415947333],
['id'=>8,'uid'=>23,'status'=>'离开','time'=>1415997332],
['id'=>9,'uid'=>23,'status'=>'进入','time'=>1416947333],
];
foreach($results as $result){
    if(!isset($data[$result['uid']])){
        $data[$result['uid']]=[];
    }
    $data[$result['uid']] += [$status[$result['status']]=>$result['time']];
}
print_r($data);
$data = array_values($data);
print_r($data);</code>

You can loop the array, and the new array will save the leaving and entering times with id as the key. Finally, remove the key from the new array to get the format you want. But this requires querying all the data

<code><?php
$data = ['id'=>1,'stauts'=>'离开','time'=>1415947332],['id'=>1,'stauts'=>'进入','time'=>1415947333];    //源数据
$result = array();
foreach($data as $tmp){
    isset($result[$tmp['id']]) or $result[$tmp['id']] = array();
    switch($tmp['status']){
        case '进入' : 
            $result[$tmp['id']]['begin_time'] = $tmp['time'];
            break;
         case '离开' : 
            $result[$tmp['id']]['end_time'] = $tmp['time'];
            break;
    }
}
print_r($result);</code>

<code><?php
$results = [
['id'=>1,'uid'=>22,'status'=>'离开','time'=>1415947332],
['id'=>2,'uid'=>22,'status'=>'进入','time'=>1415947333],
['id'=>3,'uid'=>22,'status'=>'离开','time'=>1415997332],
['id'=>4,'uid'=>22,'status'=>'进入','time'=>1416947333],
['id'=>6,'uid'=>23,'status'=>'离开','time'=>1415947332],
['id'=>7,'uid'=>23,'status'=>'进入','time'=>1415947333],
['id'=>8,'uid'=>23,'status'=>'离开','time'=>1415997332],
['id'=>9,'uid'=>23,'status'=>'进入','time'=>1416947333],
];
$data=array();
array_sort($results,'time','asc');
foreach($results as $res){
    if($res['status']=='进入'){
        foreach($results as $res1){
            if($res1['status']=='离开' && $res['time']<$res1['time']){
                    $data[]=array('begin_time'=>$res['time'],
                    'end_time'=>$res1['time'],);
                       break;
            }
        }
    }
}
var_dump($data);
</code>

The general idea should be like this. This multiple loops are time-consuming and will be very slow when there is a lot of data. There are more optimized methods, such as deleting the second layer of loops first, and then unsetting them after matching with a certain column. Of course, this requires separating the second-level loop array from the first-level array

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An algorithm problem, please give me some advice

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