decbin():Binary equivalent of decimal number

<?Php
echo decbin(3); // Output 11 
echo "<br>";
echo decbin(35); // Output 100011 
echo "<br>";
echo decbin(100); // Output is 1100100
echo "<br>";
echo decbin(258); // Output is 100000010
echo "<br>";
echo decbin(1000); // Output is 1111101000
echo "<br>";
?>

string decbin(int $number);

Example 1: Converting Negative Numbers to Binary

<?php
echo decbin(-5);  // Output: '-101' (Two's complement is not handled by decbin)
?>

Example 2: Converting Large Decimal Numbers to Binary

<?php
echo decbin(9999999);  // Output: 100110001001011001111111
?>

Example 3: Using Binary Numbers for Bitwise Operations

<?php
$a = 5;  // 101 in binary
$b = 3;  // 11 in binary
echo decbin($a & $b);  // Output: 1 (bitwise AND)
?>

Example 4: Padding Binary Numbers with Leading Zeros

<?php
$number = 7;
echo str_pad(decbin($number), 8, '0', STR_PAD_LEFT);  // Output: 00000111
?>

Example 5: Converting Multiple Decimal Numbers in a Loop

<?php
$numbers = [2, 4, 8, 16];
foreach ($numbers as $num) {
    echo "Decimal: $num => Binary: " . decbin($num) . "<br>";
}
?>

Example 6: Converting Decimal to Binary and Back to Decimal

<?php
$decimal = 25;
$binary = decbin($decimal);
echo "Binary: $binary <br>";
echo "Back to Decimal: " . bindec($binary);  // Output: 25
?>

Example 7: Handling Binary with Different Lengths

<?php
$decimal1 = 5;  // 101 in binary
$decimal2 = 32; // 100000 in binary
echo str_pad(decbin($decimal1), 6, '0', STR_PAD_LEFT);  // Output: 000101
echo "<br>";
echo str_pad(decbin($decimal2), 6, '0', STR_PAD_LEFT);  // Output: 100000
?>

Subhendu Mohapatra

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