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PHP PHP Arrays and Control Structures PHP Loops For Looping

Help using isset within For Loops

I cant figure out how to use isset() within my For Loop. I read the examples on the PHP site but they do not make sense to me. Any help would be greatly appreciated!

This is the challenge: Within the FOR loop, after displaying the number, add a conditional that uses the function isset (see documentation) to test if the incremented value equals one of the keys in the $facts array. If there is a key that matches, display the value AFTER the number.

NOTE: all numbers between 1 and 100 should still be displayed

my code is attached. thank you!

$facts = array(
    57 => ' on Heinz ketchup bottles represents the number of varieties of pickles the company once had.',
    2 => ' is the approximate hours a day Giraffes sleeps',
    18 => ' is the average hours a Python sleeps per day',
    10 => ' per cent of the world is left-handed.',
    11 => ' Empire State Buildings, stacked one on top of the other, would be required to measure the Gulf of Mexico at its deepest point.',
    98 => '% of the atoms in your body are replaced every year',
    69 => ' is the largest number of recorded children born to one woman',
//add your loop below this line
for ($i = 0; ++$i <= 100;) {
    echo $i  .  "<br/>\n";

1 Answer

Matthew Underhill
Matthew Underhill
20,324 Points

Use an if statement to check if the array key exists. If it doesn't just display the for loop number.

for ($i = 1; $i <= 100; $i++) {
    if (isset($facts[$i])) {
           echo $i . $facts[$i];
    } else {
           echo $i  .  "<br/>\n";