1, Basic classification of operators

• Arithmetic operator
• Assignment Operators
• Comparison operator
• Logical operator
• Bitwise Operators
• Other Operators

2, Arithmetic operator

Arithmetic operator is an operator that operates on numeric type variables.

(1) List of arithmetic operators

(2) Case demonstration

package main
import "fmt"

func main() {
    // + - * / % ++ --case

    var a int = 12
    var b int = 7

    fmt.Println(a + b) // 19
    fmt.Println(a - b) // 5
    fmt.Println(a * b) // 84
    fmt.Println(a / b) // 1 Redefine if you need to be a floating point number a Floating point number 12.0 var a float32 = 12.0
    fmt.Println(a % b) // 5
    a++
    fmt.Println(a) // 13
    a--
    fmt.Println(a) //12
    
}

(3) Precautions

• The division sign "/". There is a difference between integer division and decimal division. The division between integers only retains the integer part and discards the decimal part
• When modulo a number, it can be equivalent to a% B = a - A / b * B
• In Go, self increasing and self decreasing can only be used as an independent language, not c = a + +, but only a++
• The + + and -- in Go can only be written after the variable, not in front of the variable, that is, there is only a + +, but no + + a  

3, Assignment operator

Assignment operator is to assign the value of an operation to a specified variable.

(1) List of assignment operators

(2) Case demonstration

package main

import "fmt"

func main() {
    // exchange a,b Value of two numbers
    a := 2
    b := 5
    fmt.Printf("Before exchange a=%v,b=%v",a,b) //Before exchange a=2,b=5
    //Define an intermediate variable temp
    temp := a
    a = b
    b = temp
    fmt.Printf("After exchange a=%v,b=%v",a,b) //After exchange a=5,b=2

}

• The assignment operator evaluates from right to left
• The left side of an assignment operator can only be a time variable, and the right side can be a time variable, expression, or constant value

package main

import "fmt"

func main() {
    //exchange a,b The value of two numbers. Intermediate variables are not allowed
    a := 2
    b := 5

    a = a + b
    b = a - b // b = a + b - b
    a = a - b // a = a - (a-b) 
    fmt.Printf("After exchange a=%v,b=%v",a,b) //After exchange a=5,b=2

}

package main

import "fmt"

func main() {
    // Find the maximum of the three numbers
    // First find the maximum of the two numbers, and then find the third one

    a := 10
    b := 35
    c := 25
    
    var max int

    if a > b {
        max = a
    } else {
        max = b
    }

    fmt.Printf("The maximum value of the two numbers is%v", max) //35

    if c > max {
        max = c
    }

    fmt.Printf("The maximum value of the three numbers is%v", max) //35

}

  4, Relational operator

Relational operators are often used in conditional statements or loop structures of if structures, and their results are bool type (true/false).

(1) List of relational operators

(2) Case demonstration

package main

import "fmt"


func main() {

    var a int = 5
    var b int = 3

    fmt.Println(a==b) //false
    fmt.Println(a!=b) //true
    fmt.Println(a<b) //false
    fmt.Println(a>b) //true
    fmt.Println(a<=b) //false
    fmt.Println(a>=b) //true

}

  5, Logical operator

It is used to connect multiple relational expressions, and the result is also a value of bool type.

(1) List of logical operators

Suppose the value of A is true and the value of B is false:

(2) Case demonstration

package main

import "fmt"

func main() {

    var A bool = true
    var B bool = false

    fmt.Println(A&&B) //false
    fmt.Println(A||B) // true
    fmt.Println(!(A&&B)) //true
}

(3) Precautions

• &&It is also called short circuit and. If the first condition is false, the second condition will not judge the final result as false
• ||It is also called short circuit or. If the first condition is true, the second condition will not be judged, and the final result is true

6, Bitwise operator

Bit operators involve binary related contents, which are listed as follows:

7, Other operators

(1) Pointer correlation

(2) Ternary operator

Ternary operators are not supported in Go language. If you want to achieve the effect of ternary operators, you need to use conditional statements to implement them.

if <condition> {
    //...

} else {
    //...

}

8, Operator priority

• In the above table, the priority decreases in turn
• Only unary operators and assignment operators operate from right to left