hackerrank.com

cavity-map.php

<?php

//https://www.hackerrank.com/challenges/cavity-map
$handle = fopen ("php://stdin","r");
fscanf($handle,"%d",$n);
$grid = array();
for($grid_i = 0; $grid_i < $n; $grid_i++)
   fscanf($handle,"%s",$grid[]);
for ($i = 1; $i < $n -1 ; ++$i){
    for ($j = 1 ; $j < $n -1 ; ++$j){
        if ($grid[$i][$j] > $grid[$i - 1][$j] &&
            $grid[$i][$j] > $grid[$i + 1][$j] &&
            $grid[$i][$j] > $grid[$i][$j - 1] &&
            $grid[$i][$j] > $grid[$i][$j + 1]) {
            $grid[$i][$j]='X';
        }
    }
}
foreach ($grid as $value) {
    echo $value."\n";
}

game-of-thrones.php

<?php

//https://www.hackerrank.com/challenges/game-of-thrones
$_fp = fopen("php://stdin", "r");
fscanf($_fp,"%s",$pass);
$pass_array = str_split($pass);
$number_of_values = array_count_values($pass_array);
//print_r($number_of_values);
if(strlen($pass) % 2 == 1){
    $can_be_odd = True;
} else {
    $can_be_odd = False;
}
foreach ($number_of_values as $value) {
    if($value % 2 == 1){
        if($can_be_odd){
            $can_be_odd = False; //No longer can be odd!
        } else {
            echo 'NO';
            die();
        }
        
    }
}
echo "YES";

time-conversion.php

<?php

//https://www.hackerrank.com/challenges/time-conversion
$handle = fopen ("php://stdin","r");
fscanf($handle,"%s",$time);
$hh = substr($time, 0, 2);
if ($time[8] == 'P') { // For 12:00:00PM
    if ($hh != 12){
        $hh += 12;
    }
    echo $hh.substr($time, 2, 6);
} else {
    if ($hh != 12){ //For 12:00:00AM
        echo substr($time, 0, 8);
    }
    else {
        $hh = '00';
        echo $hh.substr($time, 2, 6);
    }
}