AM PM格式的两个日期变量之间的日期差异。 [重复]

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Getting the difference between two time/dates using php?

I have two dates variable let $arrival_time="7.30 AM"; $departure_time="8.30 PM";

Then how can I calculate the time difference between these two variables in php ?

<?php   
$arrival_time="7.30 AM";
$departure_time="8.30 PM";

$d1=  strtotime($arrival_time);
$d2=  strtotime($departure_time);

$diff=$d2-$d1;

//Print the difference in hours : minutes
echo date("H:i",$diff);
?>

<?php
$am = "7:30AM";
$pm = "8:30PM";
$minutes_diff = round(abs(strtotime($pm) - strtotime($am)) / 60);