Python 函数特性、递归、切片

# pass by list
def calc(nums) :
    ans = 0
    for num in nums :
        ans += num
    print(ans)

# Change Parameter, it can pass zero or many parameters
# and Parameter are treated as tuple
def per(name, *oth) :
    print(name, 'and', oth)

#keywords parameter, it are treated as dict
def keyParameter(name, **oth) :
    print(name, oth)

# 命名关键字参数
def person(name, age, *, city, job) :
    print(name, age, city, job)

def dfs(n) :
    if n < 1 : return 1
    if n == 1 or n == 2 : return 1
    return dfs(n - 1) + dfs(n - 2)

# slice function
def slice() :
    list = [1, 2, 3, 4, 5]
    print(list[0:3])
    print(list[:3])
    print(list[:-2])
    print(list[-2:-1])
    print(list[-3:])
    print(list[:4:2])
    print(list[::2])
    print(list[:])

if __name__ == '__main__' :
    ls = [1, 2, 3]
    # calc(ls)
    # per('ygl', 30)
    # keyParameter('ygl', age=17)
    # person('ygl', 21, 'bb', 'stu') error
    # person('ygl', 21, city = 'bb', job = 'stu')
    # print(dfs(5))
    slice()