PHP检查数组中的日期是否重叠

function checkDateOverlap($dates) {
    $numDates = count($dates);
    
    for ($i = 0; $i < $numDates; $i++) {
        $start1 = strtotime($dates[$i]['start']);
        $end1 = strtotime($dates[$i]['end']);
        
        for ($j = $i + 1; $j < $numDates; $j++) {
            $start2 = strtotime($dates[$j]['start']);
            $end2 = strtotime($dates[$j]['end']);
            
            if (($start1 >= $start2 && $start1 <= $end2) || ($start2 >= $start1 && $start2 <= $end1)) {
                return true; // 日期重叠
            }
        }
    }
    
    return false; // 日期不重叠
}

$dates = array(
    array('start' => '2022-01-01', 'end' => '2022-01-05'),
    array('start' => '2022-01-03', 'end' => '2022-01-07'),
    array('start' => '2022-01-06', 'end' => '2022-01-10')
);

if (checkDateOverlap($dates)) {
    echo "日期重叠";
} else {
    echo "日期不重叠";
}