# 第五堂 python四大基本型態、結構
# List 陣列、串列
### list是有序的
```python=
string = "String"
for s in string:
print(s)
# "String" => "S","t","r","i","n","g"
```
# Tuple 元組
### tuple是有序的
跟list很像,但差別在於 初始值不能改變
## 初始化方法 Tuple
```python=
t1 = tuple()
t2 = ()
print(t1)
print(t2)
```
## 初始值給了之後不能再修改
```python=
t = (1,2,3)
t[0] = 5
```
# Dict 字典
一個對應一個,Key對應到Value
像字典一樣,一個名詞對應到一個解釋

```python=
d = {
"a":"abc",
"b":"bcd"
}
print(d)
print(d['a'])
print(d['b'])
```
要用到的東西一定要在字典內,否則會產生KeyError錯誤
```python=
d = {
"a":"abc",
"b":"bcd",
"ab":"1231213",
5: "這是五"
}
print(d)
print(d['ab'])
print(d['a'])
print(d['b'])
print(d[5])
# 只會印出完全一樣的key(鍵)的值,
# 會找完全一樣的Key來做對應
# dict的key中可以同時有數字、字串
```
### dict是無序的,沒有前後順序
```python=
d = {
"cat":"小貓",
"dog":"小狗",
"bird":"小鳥",
"fish":"魚",
}
print(d['cat'])
for i in d:
print("key:", i, " value:", d[i])
```
# Set 集合
### set是無序的
Set跟Dict都是用大括號{},
特點在於,會把重複的東西自動去除
```python=
s = set()
s = {1,2,3,1,2,3,"1","2","3"}
print(s)
```
去除重複的資料
```python=
l = ["小明","小華","小東","小明"]
print(l)
print(set(l)) # 把list轉成set
```