rustleaf 0.1.0

A simple programming language interpreter written in Rust
Documentation 
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// <p>A palindromic number reads the same both ways. The largest palindrome made from the product of two $2$-digit numbers is $9009 = 91 \times 99$.</p>
// <p>Find the largest palindrome made from the product of two $3$-digit numbers.</p>

fn is_palindrome(n) {
    var s = str(n);
    var chars = s.to_list();
    var len = chars.len();
    
    for i in range(int(len / 2)) {
        if chars[i] != chars[len - 1 - i] {
            return false;
        }
    }
    true
}

fn solve_euler_004(min_digits, max_digits) {
    var largest_palindrome = 0;
    var found_a = 0;
    var found_b = 0;
    
    // Start from the largest numbers and work down
    for a in range(max_digits, min_digits - 1, -1) {
        for b in range(a, min_digits - 1, -1) {
            var product = a * b;
            
            // Early termination: if product is smaller than current best, skip
            if product <= largest_palindrome {
                break;
            }
            
            if is_palindrome(product) {
                largest_palindrome = product;
                found_a = a;
                found_b = b;
            }
        }
    }
    
    return [largest_palindrome, found_a, found_b];
}

// Test with 2-digit numbers
var test_result = solve_euler_004(10, 99);
assert(test_result[0] == 9009);
assert(test_result[1] == 99);
assert(test_result[2] == 91);

// Solve the actual problem with 3-digit numbers
var result = solve_euler_004(100, 999);
print("The largest palindrome made from the product of two 3-digit numbers is: ${result[0]}");
print("It is the product of ${result[1]} x ${result[2]}");
assert(result[0] == 906609);