# Duncan's blog

## October 9, 2014

### Project Euler: problem 30 (PHP) – Digit fifth powers

Filed under: PHP,Project Euler — duncan @ 8:00 am

I previously blogged about this Project Euler puzzle nearly 6 years ago, using Python.  This is my approach using PHP as a simple practical exercise for myself, and I’d appreciate any feedback on my PHP code.

Problem 30:

Surprisingly there are only three numbers that can be written as the sum of fourth powers of their digits:

1634 = 14 + 64 + 34 + 44
8208 = 84 + 24 + 04 + 84
9474 = 94 + 44 + 74 + 44

As 1 = 14 is not a sum it is not included.

The sum of these numbers is 1634 + 8208 + 9474 = 19316.

Find the sum of all the numbers that can be written as the sum of fifth powers of their digits.

Code:

```<?php
\$powers = [];
\$grandtotal = 0;

foreach (range(2, 354294) as \$i) {
\$total = 0;

for (\$j = 0; \$j < strlen(\$i); \$j++) {
\$total += pow(substr(\$i, \$j, 1), 5);
}

if (\$total == \$i) {
\$powers[] = \$i;
}
}

foreach (\$powers as \$i) {
\$grandtotal += \$i;
}

echo \$grandtotal;
```

Nothing too fancy, very similar to my Python approach.