📘 Week 3：函數與模組化

重點：參數傳遞、回傳值、作用域
練習：追蹤函數呼叫鏈

Day 15：定義與呼叫函數

def greet():
    print("早安！")

greet()
def say_hello(name):
    print("你好，" + name)

say_hello("會安")
def add(a, b):
    print("總和是:", a + b)

add(3, 5)
def square(x):
    print("平方是:", x ** 2)

square(4)

Day 16：回傳值與運算

def get_area(length, width):
    return length * width

print(get_area(5, 3))
def double(n):
    return n * 2

result = double(6)
print("結果:", result)
def get_discount(price, rate):
    return price * (1 - rate)

print(get_discount(100, 0.2))
def is_even(n):
    return n % 2 == 0

print(is_even(4))

Day 17：函數中的條件判斷

def check_score(score):
    if score >= 60:
        return "及格"
    else:
        return "不及格"

print(check_score(75))
def grade(score):
    if score >= 90:
        return "優"
    elif score >= 75:
        return "甲"
    else:
        return "乙"

print(grade(88))
def is_adult(age):
    return age >= 18

print(is_adult(20))
def classify_temp(temp):
    if temp > 30:
        return "炎熱"
    elif temp < 15:
        return "寒冷"
    else:
        return "舒適"

print(classify_temp(22))

Day 18：函數中的迴圈

def repeat_message(msg, times):
    for i in range(times):
        print(msg)

repeat_message("早安", 3)
def print_squares(n):
    for i in range(1, n+1):
        print(i ** 2)

print_squares(5)
def list_items(items):
    for item in items:
        print("項目:", item)

list_items(["蘋果", "香蕉", "芒果"])
def countdown(n):
    while n > 0:
        print(n)
        n -= 1

countdown(3)

Day 19：函數作用域

def show_name():
    name = "會安"
    print(name)

show_name()
# print(name)  # 這行會錯誤，因為 name 是區域變數
total = 0

def add_to_total(x):
    global total
    total += x

add_to_total(5)
print("總和:", total)
def outer():
    x = "外層"
    def inner():
        print("內層:", x)
    inner()

outer()
def multiply(a, b):
    result = a * b
    return result

print(multiply(3, 4))

Day 20：函數鏈呼叫

def add(a, b):
    return a + b

def square(x):
    return x ** 2

print(square(add(2, 3)))
def greet(name):
    return f"你好，{name}"

def welcome(name):
    message = greet(name)
    print(message)

welcome("會安")
def get_tax(price):
    return price * 0.05

def get_total(price):
    return price + get_tax(price)

print(get_total(100))
def square(x):
    return x * x

def cube(x):
    return x * square(x)

print(cube(3))

Day 21：模組與導入

import math
print("平方根:", math.sqrt(16))
import random
print("隨機數:", random.randint(1, 10))
from datetime import datetime
now = datetime.now()
print("現在時間:", now)
import statistics
scores = [80, 90, 100]
print("平均分:", statistics.mean(scores))