rustleaf 0.1.0

A simple programming language interpreter written in Rust
Documentation 
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// <p>The sum of the squares of the first ten natural numbers is,</p>
// $$1^2 + 2^2 + ... + 10^2 = 385.$$
// <p>The square of the sum of the first ten natural numbers is,</p>
// $$(1 + 2 + ... + 10)^2 = 55^2 = 3025.$$
// <p>Hence the difference between the sum of the squares of the first ten natural numbers and the square of the sum is $3025 - 385 = 2640$.</p>
// <p>Find the difference between the sum of the squares of the first one hundred natural numbers and the square of the sum.</p>

fn solve_euler_006(n) {
    // Sum of squares: 1^2 + 2^2 + ... + n^2
    var sum_of_squares = range(1, n + 1)
        .map(|x| x * x)
        .reduce(|a, b| a + b, 0);
    
    // Square of sum: (1 + 2 + ... + n)^2
    var sum = range(1, n + 1)
        .reduce(|a, b| a + b, 0);
    var square_of_sum = sum * sum;
    
    // Return the difference
    square_of_sum - sum_of_squares
}

// Test with the example (first 10 natural numbers)
var test_sum_of_squares = range(1, 11).map(|x| x * x).reduce(|a, b| a + b, 0);
assert(test_sum_of_squares == 385);

var test_sum = range(1, 11).reduce(|a, b| a + b, 0);
assert(test_sum == 55);
assert(test_sum * test_sum == 3025);

var test_result = solve_euler_006(10);
assert(test_result == 2640);

// Solve the actual problem (first 100 natural numbers)
var result = solve_euler_006(100);
print("The difference between the sum of squares and square of sum for first 100 numbers is: ${result}");
assert(result == 25164150);