python input函数

# python3
d=float(input('Please enter what is your initial balance: \n'))
p=float(input('Please input what is the interest rate (as a number): \n'))
Please enter what is your initial balance:
50000
Please input what is the interest rate (as a number):
2.3

# python2
>>>a = input("input:")
input:123                  # 输入整数
>>> type(a)
<type 'int'>               # 整型
>>> a = input("input:")
input:"runoob"           # 正确，字符串表达式
>>> type(a)
<type 'str'>             # 字符串
>>> a = input("input:")
input:runoob               # 报错，不是表达式,输入的runoob必须用括号括起来
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<string>", line 1, in <module>
NameError: name 'runoob' is not defined
<type 'str'>

# python2
>>>a = raw_input("input:")
input:123
>>> type(a)
<type 'str'>              # 字符串
>>> a = raw_input("input:")
input:runoob
>>> type(a)
<type 'str'>              # 字符串
>>>