rustleaf 0.1.0

A simple programming language interpreter written in Rust
Documentation 
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// <p>A Pythagorean triplet is a set of three natural numbers, $a \lt b \lt c$, for which,
// $$a^2 + b^2 = c^2.$$</p>
// <p>For example, $3^2 + 4^2 = 9 + 16 = 25 = 5^2$.</p>
// <p>There exists exactly one Pythagorean triplet for which $a + b + c = 1000$.<br>Find the product $abc$.</p>

fn solve_euler_009(target_sum) {
    // For a < b < c and a + b + c = target_sum
    // We know c = target_sum - a - b
    // And a^2 + b^2 = c^2
    // So a^2 + b^2 = (target_sum - a - b)^2
    
    for a in range(1, target_sum / 3) {
        for b in range(a + 1, (target_sum - a) / 2) {
            var c = target_sum - a - b;
            
            if a * a + b * b == c * c {
                return [a, b, c, a * b * c];
            }
        }
    }
    
    // Should not reach here if a solution exists
    [0, 0, 0, 0]
}

// Test with the example (3, 4, 5 triplet)
assert(3 * 3 + 4 * 4 == 5 * 5);
assert(3 + 4 + 5 == 12); // This sums to 12, not 1000

// Test our function with a smaller case
// Find triplet that sums to 12
var test_result = solve_euler_009(12);
assert(test_result[0] == 3);
assert(test_result[1] == 4);
assert(test_result[2] == 5);
assert(test_result[3] == 60);

// Solve the actual problem (sum = 1000)
var result = solve_euler_009(1000);
print("The Pythagorean triplet with sum 1000 is: ${result[0]}, ${result[1]}, ${result[2]}");
print("The product abc is: ${result[3]}");
assert(result[0] == 200);
assert(result[1] == 375);
assert(result[2] == 425);
assert(result[3] == 31875000);