迴圈 Loop

For loop
for loop在python中的語法為:
for item in sequence sequence為要迴圈的序列，item為序列中的元素，for迴圈會將序列中的元素依序取出，然而在Python中序列類型的物件有list、tuple、range、其中string也可以放進迴圈裡

#%% For loop
nums = [1,2,3,4,5]

for num in nums:
    if num == 3:
        print('Found!')
        # break
        continue
    print(num)

double for loop

#%% Double for loop
for num in nums:
    for letter in 'abc':
        print(num, letter)

內建函式 Built-in function: range()

range函式語法為: range(start, stop[, step])

#%% built-in function: range()
for i in range(1,10):
    print(i)

While loop

#%% while loop
x = 0
while x < 10:
    if x == 5:
        break
    print(x)
    x += 1

#%% Infinity loop: with interruption key "Ctrl+C"
x = 10
while True:
    print(x)
    x += 1

之後還會介紹用break/ continue的流程控制語法來控制loop迴圈