Python 高阶函数

l = [1, 2, -1, -2, 5, 6, -9]
# print([i for i in l if i > 0])
ret = filter(lambda item: item > 0, l)
print(list(ret))

l2 = ["张三", "李四", "张三丰"]
print(list(filter(lambda i: i.startswith("张"), l2)))

# map 映射
l = [1, 2, -1, -2, 5, 6, -9]
print(list(map(lambda item: item * item, l)))
# [1, 4, 1, 4, 25, 36, 81]
l3 = [1, 2, 3]
l4 = [4, 5, 6]
print(list(map(lambda x, y: x * y, l3, l4)))