Basic PHP needs new eyes to find problem

[JacksonSoccerBoy]

Im trying to create a website that will find the sum of all integers up to the number entered (ex. 5 would be 1+2+3+4+5= 15)

 

I cant get this to work It has to be something simple Im over looking

Thanks in advance 

 

<code>

 

<?php

 

$num = $_GET["loop"];

$first = 0;

$answer = 0;

 

while ($num <= $first)

{

 

$first++;

$answer == $first + $answer;

PRINT $first;

 

} 

 

 

PRINT "The sum of the numbers from 1 through $num is ";

PRINT $answer;

 

?>

 

 

</code>

[ratcateme]

try this

while ($num >= $first)
{

$first++;
$answer = $first + $answer;
PRINT $first;

} 

 

Scott.

[Maq]

What is your output?

[ratcateme]

>= should just be > other wise it goes one to far

[genericnumber1]

That's inefficient, use Faulhaber's formula.

 

$num = 101;
echo ($num * ($num + 1) / 2);

 

Edit: fitting it into your script...

 

<?php
$num = $_GET['loop'];
$sum = $num * ($num + 1) / 2;

echo "The sum of the numbers from 1 through $num is $sum";
?>

[JacksonSoccerBoy]

What is your output?

 

<output>

 

The sum of the numbers from 1 through 5 is 0

 

</output>

 

should say:

 

The sum of the numbers from 1 through 5 is 15

[JacksonSoccerBoy]

That's inefficient, use Faulhaber's formula.

 

$num = 101;
echo ($num * ($num + 1) / 2);

 

Edit: fitting it into your script...

 

<?php
$num = $_GET[lloopl];
$sum = $num * ($num + 1) / 2;

echo "The sum of the numbers from 1 through $num is $sum";
?>

 

THANKS and to think I spent an hour troubleshooting what was wrong with my code when simple math would have done the trick