Solution: Alejandro L. Herrero

arrays.php

@@ -0,0 +1,26 @@
+<?php
+
+    $arr = ["text", "random"];
+    $arrWhoNum = [1, 2, 6, 0, 5];
+    $arrMulti  = ["multidimension", $arr, $arrWhoNum];
+
+    echo count($arr); // 2;
+    echo "<hr>";
+
+    $arrMerge = array_merge($arr, $arrWhoNum);
+    echo"<pre>";
+    print_r($arrMerge); 
+    echo"</pre>";
+    echo "<hr>";
+
+    echo end($arrWhoNum); // 5
+    echo "<hr>";
+
+    $arrAdd = $arrWhoNum;
+    array_push($arrAdd, 9);
+    echo"<pre>";
+    print_r($arrWhoNum); // origin
+    print_r($arrAdd); // 9 pushed
+    echo"</pre>";
+
+?>

conditionals.php

@@ -0,0 +1,60 @@
+<?php
+
+    $date = new DateTime;
+    if ($date->format( 'N' ) == 1) {
+        echo "We are on Monday";
+    } else {
+        echo "We are not on Monday";
+    }
+
+    echo "<hr>";
+
+    if ($date->format( 'm' ) == 10) {
+        echo "We are in October";
+    } else {
+        echo "We are not in October";
+    }
+
+    echo "<hr>";
+
+    if ($date->format( 'i' ) < 10) {
+        echo "The current minute is less than 10";
+    } else if ($date->format( 'i' ) > 15) {
+        echo "The current minute is more than 15";
+    } else {
+        echo "Does not meet any conditions";
+    }
+
+    echo "<hr>";
+
+    switch ($date->format( 'N' )) {
+        case '1':
+            echo "Today is a working day";
+            break;
+
+        case '2':
+            echo "Today is a working day";
+            break;
+
+        case '3':
+            echo "Today is a working day";
+            break;
+
+        case '4':
+            echo "Today is a working day";
+            break;
+
+        case '5':
+            echo "Today is a working day";
+            break;
+
+        case '6':
+            echo "Today is not a working day";
+            break;
+
+        case '7':
+            echo "Today is not a working day";
+            break;
+    }
+
+?>

dates.php

@@ -0,0 +1,10 @@
+<?php
+
+    $date = new DateTime;
+    echo $date->format("Y-m-d") . "<br><hr>"; // <-- Current date YYYY-MM-DD format
+    echo $date->format("m-Y-d \T H:i:s") . "<br><hr>"; //<-- Different format w/ time
+    echo $date->format("d") . "<br><hr>"; // <-- Today's day
+    echo $date->format("m") . "<br><hr>"; // <-- Today's month
+    echo $date->format("i") . "<br><hr>"; // <-- Current minutes
+
+?>

functions.php

@@ -0,0 +1,55 @@
+<?php
+
+    function add($x, $y) {
+        return $x + $y;
+    }
+    echo add(2, 3); // 5
+    echo "<hr>";
+
+    function multiply($x, $y) {
+        return $x * $y;
+    }
+    echo multiply(2, 3); // 6
+    echo "<hr>";
+
+    function divide($x, $y) {
+        return $x / $y;
+    }
+    echo divide(2, 3); // 0.66667
+    echo "<hr>";
+
+    function operate($op, $x, $y) {
+        switch ($op) {
+            case 'add':
+                return add($x, $y);
+                break;
+
+            case 'subtract':
+                return $x - $y;
+                break;
+
+            case 'multiply':
+                return multiply($x, $y);
+                break;
+
+            case 'divide':
+                return divide($x, $y);
+                break;
+
+            case 'power':
+                return $x ** $y;
+                break;
+
+            case 'root':
+                return $x ** (1/$y);
+                break;
+
+            default:
+                return "Error: Invalid arguments";
+                break;
+        }
+    }
+    echo operate("root", 32, 5); // 2
+    echo "<hr>";
+
+?>

iterators.php

@@ -0,0 +1,38 @@
+<?php
+
+    for ($i = 0; $i <9; $i++) {
+        $solarSystem = ["Sun", "Mercury", "Venus", "Earth", "Mars", "Jupiter", "Saturn", "Uranus", "Neptune"];
+        if ($i == 0) {
+            echo "<h2>$solarSystem[$i]</h2><ol>";
+        } else if ($i == 8) {
+            echo " <li>$solarSystem[$i]</li></ol>";
+
+        } else {
+            echo " <li>$solarSystem[$i]</li>";
+        }
+    }
+
+    echo "<hr>";
+
+    $a = [1, 2, 3, 4, 5, 6, 7, 8, 4, 9];
+    $aTimes2 = [];
+    foreach ($a as $n) {
+        array_push($aTimes2, $n*2);
+    }
+    echo "<pre>";
+    print_r ($a);
+    print_r ($aTimes2);
+    echo "</pre>";
+
+    echo "<hr>";
+
+    $i = 0;
+    while ($i < 1) {
+        echo "- <q>What's tatoes, precious? Tell us!</q> <br><br>";
+        $i++;
+    }
+    do {
+        echo "- <q>Po-ta-toes! Boil'em, mash'em, stick'em in a stew - even you couldn't say no to that!</q>";
+    } while ($i < 0);
+
+?>

maths.php

@@ -0,0 +1,44 @@
+<?php
+
+    $a = -3.87;
+
+    $abs = abs($a);
+    echo abs($abs); // 3.87
+    echo "<hr>";
+
+    $rou = round($a);
+    echo round($rou); // -4
+    echo "<hr>";
+
+    function highestNum () {
+        $nums = func_get_args();
+        $highestNum = $nums[0];
+        foreach ($nums as $n) {
+            if ($n > $highestNum) {
+                $highestNum = $n;
+            }
+        }
+        return $highestNum;
+    }
+    $result = highestNum(2, 4, 6, 2, 7, 4, 8, 5); 
+    echo $result; // 8
+    echo "<hr>";
+
+    function lowestNum () {
+        $nums = func_get_args();
+        $lowestNum = $nums[0];
+        foreach ($nums as $n) {
+            if ($n < $lowestNum) {
+                $lowestNum = $n;
+            }
+        }
+        return $lowestNum;
+    }
+    $result = lowestNum(2, 4, 6, 2, 7, -4, 8, 5); 
+    echo $result; // -4
+    echo "<hr>";
+
+    $ran = rand();
+    echo $ran; // <-- random integer
+
+?>

operators.php

@@ -0,0 +1,33 @@
+<?php
+
+    $a = 3;
+    echo $a + (1 - 3) * 3 / 2 * $a; // -6
+    echo "<br>";
+    echo $a % 5; // 3
+
+    echo "<hr>";
+
+    $b = 2;
+    var_dump($a == $b);  // bool(false)
+    var_dump($a != $b);  // bool(true)
+    echo $a > $b;   // 1
+    echo $a < $b;   // *Nothing is displayed when a false boolean is echoed.
+    var_dump($a <= ($b + 1));   // bool(true)
+    echo $a >= $b;   // 1
+
+    echo "<hr>";
+
+    $c = false;
+    $d = true;
+
+    if ($c && $d ) { 
+        echo "Both true";
+    } else if (!$d) {
+        echo "D is not true";
+    } else if ($c xor $d) {
+        echo "One is true, not both."; // <-- First valid
+    } else if ($c || $d) {
+        echo "Any is true"; // <-- Also valid, but code was broken.
+    }
+
+?>

phpinfo.php

@@ -0,0 +1,5 @@
+<?php
+
+    phpinfo();
+
+?>

print.php

@@ -0,0 +1,24 @@
+<?php
+
+    $a = "Testing PHP";
+    print $a;
+    echo "$a <br><br>" . $a; // Starts adjacent to previous "print"
+
+    echo "<hr>";
+
+    function test() {
+        $b = 2;
+        return $a + $b; 
+    }
+    echo test(); // Drops error because $a is not in the scope of the function 
+    // BUT gives "2" stored in $b
+
+    echo "<hr>";
+
+    $b = ["This is a test", 2, true];
+
+    echo "<pre>";
+    print_r($b); 
+    echo "</pre>";
+
+?>

strings.php

@@ -0,0 +1,41 @@
+<?php
+
+    echo "text";
+    echo "<hr>";
+
+    $a = "more";
+    echo "$a text"; // more text
+    echo "<hr>";
+
+    echo $a . " and $a text"; // more and more text
+    echo "<hr>";
+
+    $b = "This is a silly example";
+    echo str_replace("silly", "test", $b); // <-- This is a test example (Replace is case sensitive)
+    echo "<hr>";
+
+    $b = "This is a SILLY example";
+    echo str_ireplace("silly", "test", $b); // <-- This is a test example (Ireplace is case INsensitive)
+    echo "<hr>";
+
+    $c = "this is some text, ";
+    echo str_repeat($c, 3); // <-- this is some text, this is some text, this is some text, 
+    echo "<hr>";
+
+    echo "'$a' is " . strlen($a) . " characters long"; //<-- 'more' is 4 characters long 
+    echo "<hr>";
+
+    echo strpos($a, "o"); // <-- 1
+    echo "<hr>";
+
+    $A = strtoupper($a);
+    echo $A; // <-- MORE
+    echo "<hr>";
+
+    echo strtolower($A); // <-- more
+    echo "<hr>";
+
+    echo substr($a, -2); // <-- re 
+    echo "<hr>";
+
+?>

types.php

@@ -0,0 +1,13 @@
+<?php
+
+    $boolean = true;
+    $integer = 3;
+    $float = 3.0;
+    $string = 'Hey';
+    $array = [1, "2", true];
+    class potato {};
+    $object = new potato;
+    $null = null;
+    echo gettype($null); // <-- Insert variable to check its type
+
+?>