<?php
 
$datatime1 = new DateTime('2015/04/15 00:00:00');
$datatime2 = new DateTime('2015/05/16 00:00:00');
 
$data1  = $datatime1->format('Y-m-d H:i:s');
$data2  = $datatime2->format('Y-m-d H:i:s');
 
$diff = $datatime1->diff($datatime2);
$horas = $diff->h + ($diff->days * 24);
$minutos = $horas * 60;
 
echo "A diferença de horas entre {$data1} e {$data2} é {$horas} horas \n";
echo "A diferença de minutos entre {$data1} e {$data2} é {$minutos} minutos";
 

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