function x_leftmost_digit($n, $x) {
$x = pow(10, $x);
while ($n > $x) {
$n = intval($n / 10);
}
return $n;
}
srand(time());
for ($i = 1; $i <= 5; $i++) {
$n = rand(1, 100000);
$x = rand(1, 5);
echo $x . " leftmost digit of " . $n . " is " . x_leftmost_digit($n, $x) . PHP_EOL;
}
/*
run:
2 leftmost digit of 1300 is 13
4 leftmost digit of 84680 is 8468
4 leftmost digit of 85552 is 8555
5 leftmost digit of 54087 is 54087
2 leftmost digit of 78053 is 78
*/