Golang Programming Examples

go êµ¬ì¡°ì²´ì™€ ë©”ì„œë“œ ì—°ê²°

golang

package main

import "fmt"


type Person struct{
    name string
    age int
}
func(p *Person) greeting(){
    fmt.Println("Hello~")
}
func (p *Student) greeting(){
    fmt.Println("Hello~ Student")
}

type Student struct{
    Person
    school string
    grade int
}

func main(){
    var s Student
    s.Person.greeting()
    s.greeting()
    
}

go êµ¬ì¡°ì²´ì™€ í¬ì¸í„°ë³€ìˆ˜

golang

package main

import "fmt"

type Rectangle struct {
    width, height int
}

func rectangleScalaA(rect *Rectangle, factor int){
    rect.width = rect.width * factor
    rect.height = rect.height * factor
}


func rectangleScalaB(rect Rectangle, factor int){
    rect.width = rect.width * factor
    rect.height = rect.height * factor
}

func main() {
    rect1 := Rectangle{30, 30}
    rectangleScalaA(&rect1, 10)
    fmt.Println(rect1) //주소를 넘겨주기 때문에 바뀐 값이 들어감
    
    rect2 := Rectangle{30, 30}
    rectangleScalaB(rect2, 10)
    fmt.Println(rect2) //값을 넘겨주기 때문에 rect2는 변하지 않음.
}

/*
    포인터 변수는
    pointerVar = &{} 형태
    그래서 &pointerVar은 주소를 나타내고
    *pointerVar는 주소의 값을 나타낸다.
*/

go ë§µì„ ë§¤ê°œë³€ìˆ˜ë¡œ ë°›ê³ ë§µì„ ë¦¬í„´í•˜ëŠ” í•¨ìˆ˜

golang

package main

import "fmt"

func main() {

    var newMap = map[string]string{
        "one" : "1",
        "two" : "2",
        "three" : "3",
    }

    fmt.Println(mapTest(newMap, "two"))
    
}

func mapTest(map1 map[string]string, key1 string) (returnMap map[string]string){
    //returnMap 선언된 상태
    //할당을 해야 함
    //할당은 = 이것으로
    returnMap = make(map[string]string)
    //or returnMap = map[string]string{}
    
    Loop : 
        for key, value := range map1 {
            if key==key1 {
                returnMap[key] = value
                break Loop
            }
        }
    return            
    
        
}

Golang Bot

golang

package main

import (
	"fmt"
	"os"
	"bufio"
	"strings"
	"time"
	"math/rand"
)

func main() {
	reader := bufio.NewReader(os.Stdin)
	fmt.Println("Enter a move (rock, lizard, paper, spock, scissors):")
	move, _ := reader.ReadString('\n')

	// Trim string
	move = strings.TrimSpace(move)

	// Have the bot make the moves
	possibleMoves := []string{"rock", "lizard", "paper", "spock", "scissors"}

	// Generate random num
	rand.Seed(time.Now().UTC().UnixNano())
	botMove := possibleMoves[randInt(0, len(possibleMoves) - 1)]

	fmt.Println("The bot guessed", botMove)

	// Calculate outcome
	switch move {
	case "rock":
		if botMove == "scissors" || botMove == "lizard" {
			win()
		} else {
			lose()
		}
	case "lizard":
		if botMove == "spock" || botMove == "paper" {
			win()
		} else {
			lose()
		}
	case "paper":
		if botMove == "rock" || botMove == "spock" {
			win()
		} else {
			lose()
		}
	case "spock":
		if botMove == "scissors" || botMove == "rock" {
			win()
		} else {
			lose()
		}
	case "scissors":
		if botMove == "paper" || botMove == "lizard" {
			win()
		} else {
			lose()
		}
	}
}

func win() {
	fmt.Println("Congratulations, you won!")
}

func lose() {
	fmt.Println("You lost! Too bad.")
}

func randInt(min int, max int) int {
    return min + rand.Intn(max-min)
}

happyday

golang

package main

import (
	"fmt"
	"time"
)

func Happy() {
    fmt.Print("\n.~~~~.\ni====i_\n|cccc|_)\n|cccc|\n`-==-'\nHappy Programmer’s day!")
}

func Work(){
    fmt.Println("go to work")
}

func main() {
	if time.Now().YearDay() == 1 << 8{
	   Happy()
	}else{
	   Work()
	}
}

Execute GO Language Online

golang

package main

import ("fmt"
    "math/rand"
)

const NUMS = 100
var num [NUMS] int

func gen_nums() {
    rand.Seed(183)
    for count := 0; count < NUMS; count++ {
        num[count] = rand.Intn(10000)
    }
}

func swap(x *int, y *int) {
    temp := *x
    *x = *y
    *y = temp
}

func main() {
    gen_nums()
    for count1 := 0; count1 < NUMS - 1; count1++ {
        for count2 := count1 + 1; count2 < NUMS; count2++ {
            if num[count1] > num[count2] {
                swap(&num[count1], &num[count2])
            }
        }
    }
    
    for count := 0; count < NUMS; count++ {
        fmt.Printf("%d\n", num[count])
    }
}

qdqwdqw

golang

package main

import "fmt"

type A interface {
    A()
}
type B interface {
    A
    B()
}

type AA struct {}
type BB struct {}

func (aa *AA) A() {
    fmt.Println("AA method A()")
}


func (bb *BB) A() {
    fmt.Println("BB method A()")
}


func (bb *BB) B() {
    fmt.Println("BB method B()")
}

func Factory(c *A) (d *A) {
    return d, nil
}

func main() {
    aa := &AA{}
    aa.A()
   fmt.Printf("hello, world\n")
}

testgo

golang

package main

import "fmt"

func main() {
   fmt.Printf("hello, world\n")
   fmt.Printf("haha")
}

Execute GO Language Online

golang

package main

import "fmt"

func main() {
   fmt.Printf("hello, world\n")
}

new Go lang

golang

//Go language
//Starting with the main package
package main
import 

int main() 

{
 e := echo.New()
 // here goes the Middleware

 e.Use(middleware.Logger())
 e.Use(middleware.Recover())

 //CORS
 e.Use(middleware.CORSWithConfig(middleware.CORSConfig{
  AllowOrigins: []string{"*"},
  AllowMethods: []string{echo.GET, echo.HEAD, echo.PUT, echo.PATCH, echo.POST, echo.DELETE},
 }))


// Server for middle wave
 e.Run(standard.New(":1323"))
}


// imported packages in server,go
// middleware in the application
// Middleware
//server log
 e.Use(middleware.Logger())
//reover in the chain
 e.Use(middleware.Recover())
//webservers cross domain access controls
 e.Use(middleware.CORSWithConfig(middleware.CORSConfig{
  AllowOrigins: []string{"*"},
  AllowMethods: []string{echo.GET, echo.HEAD, echo.PUT, echo.PATCH,    echo.POST, echo.DELETE},
 }))
//webserver for echo on 1323 port
e.Run(standard.New(":1323"))

// Route for handler 

 e.GET("/", func(c echo.Context) error {       return c.String(http.StatusOK, "Hello, World!\n")  
})

//controlers
e.POST("/users", controllers.CreateUser)

// Main Server
 e.Run(standard.New(":1323"))
}

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