fun main() {
    print("Hello, World!");
}

fun fib(n) {
	if (n <= 1) {
		ret n;
	}

	ret fib(n - 1) + fib(n - 2);
}

fun main() {
	mut n = 10;
	loop {
		if (n < 0) {
			break;
		}

		println(fib(n));
		n -= 1;
	}
}

// This is a single line comment

fun main() {
    // A variable is either const,
    const a = 1;
    // or mutable
    mut b = 2;
    const result = a + b;
    print(result); // 3
}

fun main() {
    const a = int(input());
    const b = int(input());
    
    if (a > b) {
        print("a is greater than b");
    } else if (a < b) {
        print("a is less than b");
    } else {
        print("a is equal to b");
    }
}

fun main() {
    const n = int(input());
    mut i = 1;
    
    loop {
        if (i > n) {
            break;
        }
        println(i);
        i += 1;
    }
}

fun main() {
    const arr = [1, 2, 3, 4, 5];
    print(arr[0]); // 1
    print(arr[1]); // 2
    print(arr[2]); // 3
    print(arr[3]); // 4
    print(arr[4]); // 5
    
    // iterate
    iter arr: it {
        print(it);
    }
}

fun add(a, b) {
    ret a + b;
}

data Triangle {
    AB,
    AC,
    BC
}

methods Triangle {
    fun area() {
        const s = (@AB + @AC + @BC) / 2;
        ret pow(s * (s - @AB) * (s - @BC) * (s - @AC), 0.5);
    }
}

fun main() {
    const triangle = Triangle {
        AB: 4,
        AC: 5,
        BC: 6
    };
    println(triangle.area());
}