Project Euler - Problem 6 Solution With PHP

The sum of the squares of the first ten natural numbers is, `1^2 + 2^2 + ... + 10^2 = 385`

The square of the sum of the first ten natural numbers is, `(1 + 2 + ... + 10)^2 = 552 = 3025`

Hence the difference between the sum of the squares of the first ten natural numbers and the square of the sum is `3025 − 385 = 2640`.

Find the difference between the sum of the squares of the first one hundred natural numbers and the square of the sum.

At first the `\$sum_of_squares` and `\$sums` are equal to `1`.

After calculating the hardest part (`calculating 1`) without using programming we are ready to start out `for` loop from `2` and add the second powers of the `\$number`s to `\$sum_of_squares` by also adding the `\$number` to `\$sums` each time.

``````\$sum_of_squares = \$sums = 1;

for (\$number = 2; \$number <= 100; \$number++)
{
\$sum_of_squares += (\$number * \$number);
\$sums += \$number;
}

\$result = (\$sums * \$sums) - \$sum_of_squares;
``````

At last we will need to get the second power of `\$sums` and subtract `\$sum_of_squares` from it.

Execution time: 0s