leetcode\BasicCalculatorII::calculate()

Complexity

Conditions	10
Paths	14

Size

Total Lines	33
Code Lines	25

Duplication

Lines	0
Ratio	0 %

Importance

Changes	1
Bugs	0	Features	0

<?php
    public static function calculate(string $s): int
    {
        if (empty($s)) {
            return 0;
        }
        $s = str_replace(' ', '', $s);
        $n = strlen($s);
        [$stack, $num, $operator] = [[], 0, '+'];
        for ($i = 0; $i < $n; $i++) {
            $char = $s[$i];
            if (is_numeric($char)) {
                $num = $char;
            }
            if ($i === $n - 1 || in_array($char, self::$operators)) {
                switch ($operator) {
                    case '+':
                        array_push($stack, $num);
                        break;
                    case '-':
                        array_push($stack, -$num);
                        break;
                    case '*':
                        array_push($stack, (int)(array_pop($stack) * $num));
                        break;
                    case '/':
                        array_push($stack, (int)(array_pop($stack) / $num));
                        break;
                }
                [$num, $operator] = [0, $char];
            }
        }

        return array_sum($stack);

The expression return array_sum($stack) could return the type double which is incompatible with the type-hinted return integer. Consider adding an additional type-check to rule them out.

    }