Day3: Common operators
Today introduced several operators: "arithmetic operators", "Comparison operators", "assignment operator."
I. arithmetic operators
1. The arithmetic operators
arithmetic operators is relatively simple, the following:
+ 加, - 减, * 乘, / 除, % 取模, // 整除, ** 幂
Furthermore, the space between the recommended amount and a grid operator.
2. The calculation of variable
usage is very simple, no doubt that 1 + 1 = 2 such arithmetic. We can also use arithmetic operators between variables and variables. E.g:
a = 1
b = 2
print(a + b)
The result is output3
Thus other operators are also used, such as:
a = 10
b = 5
c = 3
print(a - b) #a减b 输出结果是5
print(a * b) #a乘b 输出结果是50
print(a / b) #a除以b 输出结果是2
print(a // c) #a除以b的整数部分 输出结果是3
print(a % c) #a除以c的余数 输出结果是1
print(a ** c) #a的c次方 输出结果是1000
3. constant operation
this is very simple, it is this:
print(1 + 1) #输出结果是2
4. The operation of string
two or more strings will merge when two strings are added. Such as:
a = "abc"
b = "def"
print(a + b) #输出结果是abcdef
Between the strings and the digital multiplication may be used
a = "a"
print(a * 3) #输出结果是aaa
II. Comparison Operators
Comparison operator name suggests is used to compare the size, Python there are so few in comparison operators:
== 相等, != 不等于, > 大于, < 小于, >= 大于或等于,<= 小于或等于
We can use them:
a = 1
b = 2
print(a > b) #输出结果是False
print(a < b) #输出结果是True
You can also use the typefunction to see if the variable type a> b or a <b is what we did yesterday presented the views of Boolean values.
III. Assignment operator
Python assignment operators are just a
= 简单地赋值运算符few: += 加法赋值运算符, -= 减法赋值运算符, *= 乘法赋值运算符, /= 除法赋值运算符, %= 取模赋值运算符, //= 整除赋值运算符, ,**= 幂赋值运算符
Tell us about it, if a = 1it's a simple assignment, the assignment is to explain the value of 1 to a. for example:
a = 1 #将1的值赋值给a a就等于1了
c = a #将a的值赋值给c c就等于1了
print(c)
Other re-introduced it
a = 1 #对a进行赋值1
a += 1 #a += 1等效于a = a + 1
print(a) #所以此时的a等于2
** so, a - = 1 is a = a + 1, a / = 1 is a = a / 1 back ** I not introduced.
