php 二维数组 根据条件合并成新的二维数组

$arr = [
    0 => [
        'id' => 1,
        'name' => '张三',
        'phone' => '123456789'
    ],
    1 => [
        'id' => 2,
        'name' => '李四',
        'phone' => '456789'
    ],
    3 => [
        'id' => 1,
        'name' => '张三1',
        'phone' => '1234567890'
    ],
    4 => [
        'id' => 1,
        'name' => '张三2',
        'phone' => '12345678901'
    ],
    5 => [
        'id' => 2,
        'name' => '李四1',
        'phone' => '12345678666'
    ]
];
$arr1 = [];
foreach($arr as $v){
     
    if(!isset($arr1[$v['id']])){
        $arr1[$v['id']] = [
            'id' => $v['id'],
            'info' => [[
                'name' => $v['name'],
                'phone' => $v['phone'],
            ]],
        ];
    }else{
        $arr1[$v['id']]['info'][] = [
            'name' => $v['name'],
            'phone' => $v['phone'],
        ];
    }
}
print_r($arr1);

 

function getTree($array, $pid=1){
        $tree = [];
        foreach ($array as $key => $value) {
            if ($value['parent_code'] == $pid) {
                $value['children']= $this->getTree($array, $value['city_id']);
                if (empty($value['children'])) unset($value['children']);
                $tree[] = $value;
            }
        }
        return $tree;
    }