流程控制之for

for循环是 迭代式循环，其强大之处在于循环取值

用法一：

l = [1, 2, 3, 4, 5, 5, 6, 5, 4, 3]
for x in l:
    print(x)

info = {'name': "qzk", 'age': ''}
for x in info:
     print(x, info[x])

 # for + break
qzk = [112, 33, 44, 444]
for x in qzk:
    if x == 44:
        break
    print(x)

# for + else
qzk = [112, 33, 44, 444]
for x in qzk:
    if x == 555:
        break
    print(x)
# else 在for循环没有被break打断的时候，才执行else下面的程序。

# for + range()
# 顾头不顾尾， range(1,10,步长)python2中显示列表》》》蛋 ， 在python3中，# 只显示 range(1,10,步长)目的是为了优化内存空间
print(range(1, 10, 2))
for i in range(1, 20, 2):
    print(i)
print(range(5))

# for的嵌套
for i in range(3):
    for j in range(4):
        print(i, j)

# for 遍历列表
info = [
    ['qzk', 18, 'male'],
    ['kevin', 19, 'male'],
    ['猴', 32, 'female']
]
for item in info:
    print(item)

for name, age, gender in info:
    print('员工姓名：%s、年龄：%s、性别：%s' % (name, age, gender))