파이썬 For 구조 (for i in test_list: )

for 변수 in 리스트(또는 튜플, 문자열):
    수행할 문장1
    수행할 문장2
    ...

>>> test_list = ['one', 'two', 'three'] 
>>> for i in test_list: 
...     print(i)
... 
one 
two 
three

>>> a = [(1,2), (3,4), (5,6)]
>>> for (first, last) in a:
...     print(first + last)
...
3
7
11

# marks1.py
marks = [90, 25, 67, 45, 80]

number = 0 
for mark in marks: 
    number = number +1 
    if mark >= 60: 
        print("%d번 학생은 합격입니다." % number)
    else: 
        print("%d번 학생은 불합격입니다." % number)

>>> a = range(10)
>>> a
range(0, 10)

>>> a = range(1, 11)
>>> a
range(1, 11)

>>> add = 0 
>>> for i in range(1, 11): 
...     add = add + i 
... 
>>> print(add)
55

#marks3.py
marks = [90, 25, 67, 45, 80]
for number in range(len(marks)):
    if marks[number] < 60: 
        continue
    print("%d번 학생 축하합니다. 합격입니다." % (number+1))

>>> for i in range(2,10):        # ①번 for문
...     for j in range(1, 10):   # ②번 for문
...         print(i*j, end=" ") 
...     print('') 
... 
2 4 6 8 10 12 14 16 18 
3 6 9 12 15 18 21 24 27 
4 8 12 16 20 24 28 32 36
5 10 15 20 25 30 35 40 45
6 12 18 24 30 36 42 48 54 
7 14 21 28 35 42 49 56 63 
8 16 24 32 40 48 56 64 72 
9 18 27 36 45 54 63 72 81

>>> a = [1,2,3,4]
>>> result = []
>>> for num in a:
...     result.append(num*3)
...
>>> print(result)
[3, 6, 9, 12]

>>> a = [1,2,3,4]
>>> result = [num * 3 for num in a]
>>> print(result)
[3, 6, 9, 12]

>>> a = [1,2,3,4]
>>> result = [num * 3 for num in a if num % 2 == 0]
>>> print(result)
[6, 12]

[표현식 for 항목 in 반복가능객체 if 조건문]

[표현식 for 항목1 in 반복가능객체1 if 조건문1
        for 항목2 in 반복가능객체2 if 조건문2
        ...
        for 항목n in 반복가능객체n if 조건문n]

>>> result = [x*y for x in range(2,10)
...               for y in range(1,10)]
>>> print(result)
[2, 4, 6, 8, 10, 12, 14, 16, 18, 3, 6, 9, 12, 15, 18, 21, 24, 27, 4, 8, 12, 16,
20, 24, 28, 32, 36, 5, 10, 15, 20, 25, 30, 35, 40, 45, 6, 12, 18, 24, 30, 36, 42
, 48, 54, 7, 14, 21, 28, 35, 42, 49, 56, 63, 8, 16, 24, 32, 40, 48, 56, 64, 72,
9, 18, 27, 36, 45, 54, 63, 72, 81]