https://www.hackerrank.com/challenges/kangaroo/

kangaroo.php

<?php

// Complete the kangaroo function below.
function kangaroo($x1, $v1, $x2, $v2) {
  $xc1=$x1; $xc2=$x2;
  for($i=$x1;$i<$x2;$i++){
    $xc1+=$v1;
    $xc2+=$v2;
    if ($xc1==$xc2) return "YES";
  }
  return "NO";
}

$fptr = fopen(getenv("OUTPUT_PATH"), "w");

$stdin = fopen("php://stdin", "r");

fscanf($stdin, "%[^\n]", $x1V1X2V2_temp);
$x1V1X2V2 = explode(' ', $x1V1X2V2_temp);

$x1 = intval($x1V1X2V2[0]);

$v1 = intval($x1V1X2V2[1]);

$x2 = intval($x1V1X2V2[2]);

$v2 = intval($x1V1X2V2[3]);

$result = kangaroo($x1, $v1, $x2, $v2);
fwrite($fptr, $result . "\n");

fclose($stdin);
fclose($fptr);