Python 流程控制

TIP

流程控制包括条件判断、循环和分支，决定了代码的执行路径。

条件判断

age = 18
if age >= 18:
    print("成年人")
elif age >= 6:
    print("未成年人")
else:
    print("儿童")

for 循环

# 遍历列表
fruits = ["苹果", "香蕉", "橘子"]
for fruit in fruits:
    print(fruit)

# 遍历字典
user = {"name": "张三", "age": 25}
for key, value in user.items():
    print(f"{key}: {value}")

# 使用 range
for i in range(5):
    print(i)

# 带索引
for idx, fruit in enumerate(fruits):
    print(f"{idx}: {fruit}")

while 循环

count = 0
while count < 5:
    print(count)
    count += 1

# break 和 continue
for i in range(10):
    if i == 3:
        continue
    if i == 7:
        break
    print(i)

列表推导式

squares = [x**2 for x in range(10)]
evens = [x for x in range(20) if x % 2 == 0]