Introduction

Question 1

how to print

Answer 1

echo “string”;

Question 2

new line

Answer 2

echo “\n new line”;

Question 3

create a variable

Answer 3

$variable_name = "duck";
$variable_number = 103;
$variable_float = -349.4;

Question 4

combine string

Answer 4

echo “string one “ . “ string two”;

Question 5

print string and variable

Answer 5

echo “$variable_name is cool”;

Question 6

string and variable but adding “s or ing”

Answer 6

echo “${variable_name}s are cool”;

Question 7

append more to a string variable

Answer 7

$variable_name .= “ quack”;

Question 8

create variable copy

Answer 8

$variable_copy = $variable_name;

** is a separate variable and will stay the same even if $variable_name gets changed later

Question 9

create variable alias

Answer 9

$variable_alias &= $variable_name;

** will always point to $variable_name, even if it is changed

Question 10

math

Answer 10

\+ addition
- subtraction
* multiplication
/ division
** exponential 
% modulo (remainder)

Question 11

math short syntax

Answer 11

Operation:	Long Syntax:	Short Syntax:
Add	        $x = $x + $y	$x += $y
Subtract	$x = $x - $y	$x -= $y
Multiply	$x = $x * $y	$x *= $y
Divide	$x = $x / $y	$x /= $y
Mod	$x = $x % $y	$x %= $y

Question 12

increment operators

Answer 12

add $var++;

sub $var–;

Question 13

call multiple functions

Answer 13

echo first() . second() . third();

Question 14

function to make permanent changes to a variable

Answer 14

function addXPermanently(&$param){
     $param = $param . "X";
     return $param;
}
$word = "Hello";
addXPermanently($word); // Prints: HelloX
echo $word; // Prints: HelloX

** add & to variable

Question 15

access a global parameter in a function

Answer 15

$param = 10;
function findParam(){
     global $param;
     return $param * 2; 
}

Question 16

create a function

Answer 16

function helloWorld($param, $var){
        return $param + $var;
}