简单的几率计算

<?

$myjilv = array (//配置出现几率
'money' => array (1, 30 ), 'exp' => array (31, 50 ), 'energy' => array (51, 100 ) );
function getJilv($jilv) {
	
	$randval = mt_rand ( 1, 100 );
	foreach ( $jilv as $k => $v ) {
		if ($v != "0") {
			if ($randval >= $v [0] && $randval <= $v [1]) {
				return $k;
			}
		}
	}
}
echo getJilv( $myjilv );