/*
split_bytes(n)
--------------
Splits a 32-bit unsigned integer into its four bytes.
Layout (little-endian order):
byte[0] = lowest 8 bits
byte[1] = next 8 bits
byte[2] = next 8 bits
byte[3] = highest 8 bits
Uses bitwise AND and shifts:
n & 0xFF → extract lowest byte
(n >> 8) & 0xFF → extract next byte
...
*/
function split_bytes(int $n): array {
return [
$n & 0xFF, // lowest byte
($n >> 8) & 0xFF,
($n >> 16) & 0xFF,
($n >> 24) & 0xFF // highest byte
];
}
/*
print_bits(label, value)
------------------------
Prints an 8-bit or 32-bit value in binary.
Uses decbin() and manual zero-padding.
*/
function print_bits(string $label, int $value, int $bits): void {
$binary = decbin($value);
// Pad with leading zeros
if (strlen($binary) < $bits) {
$binary = str_repeat('0', $bits - strlen($binary)) . $binary;
}
echo "{$label} ({$bits} bits): {$binary}\n";
}
$value = 3298312;
$bytes = split_bytes($value);
echo "Bytes (little-endian order):\n";
foreach ($bytes as $i => $b) {
echo "byte[{$i}]: {$b}\n";
}
echo "\nBit representation:\n";
// Print full 32-bit value
print_bits("Full value", $value, 32);
// Print each byte in binary
foreach ($bytes as $i => $b) {
print_bits("byte[{$i}]", $b, 8);
}
/*
run:
Bytes (little-endian order):
byte[0]: 8
byte[1]: 84
byte[2]: 50
byte[3]: 0
Bit representation:
Full value (32 bits): 00000000001100100101010000001000
byte[0] (8 bits): 00001000
byte[1] (8 bits): 01010100
byte[2] (8 bits): 00110010
byte[3] (8 bits): 00000000
*/
