1252.php

<?php

class Solution
{

    /**
     * @param Integer $n
     * @param Integer $m
     * @param Integer[][] $indices
     * @return Integer
     */
    function oddCells($n, $m, $indices)
    {
        $row = [];
        $col = [];
        $odd_count = $m * $n;
        foreach ($indices as $indice) {
            if (isset($row[$indice[0]])) $row[$indice[0]] += 1;
            else $row[$indice[0]] = 1;
            if (isset($col[$indice[1]])) $col[$indice[1]] += 1;
            else $col[$indice[1]] = 1;
        }
        for ($i = 0; $i < $n; $i++) {
            for ($j = 0; $j < $m; $j++) {
                $cnt = 0;
                if (isset($row[$i])) $cnt += $row[$i];
                if (isset($col[$j])) $cnt += $col[$j];
                if ($cnt % 2 == 0) $odd_count--;
            }
        }
        return $odd_count;
    }
}