DAY 06 - 遞迴練習 & 字典

tags: python教學 函式 副程式

遞迴練習

階乘

def Fac(n):
    if n > 1:
        return n * Fac(n-1)
    else:
        return 1

print(Fac(5))

字典

設定一個新的字典時，要用大括號 { }

car = {"color":"black" , "brand":"honda"}   

color = car["color"]

print(color)

新增新的屬性

car["mileage"] = 100

修改一個原本就有的屬性

car["color"] = "white"

刪除一個原本就有的屬性

del car["mileage"]

檢視字典裡有什麼屬性(key)

print(car.keys())

---

使用.items()讓for迴圈可以遍訪字典
.keys()可以只遍訪屬性(key)
.values()可以只遍訪數值(value)

for key,value in car.items():
    print(key,end=" : ")
    print(value)

---

整理字典
sorted()

fav_fruits = {
    "alan":"apple",
    "jack":"grape",
    "rose":"lemon",
    "bonny":"banana",
    "stan":"apple"
}
for key in sorted(fav_fruits.keys()):
    print(key)

去掉重複的
set()

for value in sorted( set( fav_fruits.values() ) ):
    print(value)

字典裡塞字典

students ={
    "alan":{
        "ID":"D0001",
        "age":21,
        "city":"taipei",
    },
    "jack":{
        "ID":"D0002",
        "age":21,
        "city":"taichung",
    },
    "rose":{
        "ID":"D0003",
        "age":20,
        "city":"taichung",
    }
}

for name , infomation in st.items():
    print(name,":", infomation["ID"] , "," , infomation["city"] )

#人名: ID , city

HW: 查「河內塔」