Hello, world!

嘿嘿

1. The famous mass-energy equivalence formula: $E = mc^2$
2. The quadratic formula: $x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$
3. Euler’s identity: $e^{i\pi} + 1 = 0$

def greet(name):
    return f"Hello, {name}!"

# 测试
print(greet("World"))