圆形价格最接近$ xx.99

Question

我想将价格四舍五入（上涨或下跌）至最接近的$ xx.99

例如：

$17.99 -> Stay as is

$22.03 -> $21.99

$33.85 -> $33.99

$45 -> $44.99

Answer 1

加0.01，圆，减0.01

$input = 17.99; // example input
$add = $input + 0.01;
$round = round($add);
$output = $round - 0.01;

或一体化：

return round($input + 0.01) - 0.01;