<?php
echo round(3.14159, 2), "\n"; // 3.14
echo ceil(4.1), "\n";          // 5
echo floor(4.9), "\n";         // 4
echo max(2, 9, 5), "\n";       // 9
echo min(2, 9, 5), "\n";       // 2
echo abs(-17), "\n";           // 17
?>