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# For Loops, Challenge 1 of 2.

I'm supposed to print each number 1 through 100, including one hundred. At each of the facts' number, I'm supposed to print the fact with it. I keep getting the errors "Does not end at 100" or "I do not see all the numbers between 1 and 100."

I've looked up other solutions posted, but they're using functions I've not been taught yet.

index.php
```<?php
\$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',
);
for (\$i = 0; \$i < 101; \$i++) {
echo \$i . \$facts[\$i] . "<br />\n";
}
```

Serhii has it nailed - but if you're in the beginning stages, here's what I would say:

Here's what your loop should look like:

```for(\$i = 1; \$i <= 100; \$i++) {
if(isset(\$facts[\$i])) {
echo \$i . \$facts[\$i];
} else {
echo \$i;
}
}
```

The isset function is checking to see if there is a match for the numerical key value for wherever \$i is at in the loop at that time. If it finds a match, we echo out the number, THEN the value of the array item as per the instructions. Otherwise, if the \$i value is not part of the array's keys, it skips over the first statement and heads directly to your else statement to echo out simply \$i. I hope this helps!

Thanks very much! I didn't quite understand the isset function. This is very helpful!

Hi there Taylor!

Everything except 0 and there must be 100 at the end. This what task is saying. ;)

```for (\$i = 1; \$i <= 100; \$i++) {
echo \$i  .  "<br />\n";
}
```

But if you want to output array value, always check if there is such element in the array before outputing it.

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

Best regards.