Practice

Go exercises

Make a change, predict what it will do, and compare the result.

1
Go Basics
Print a message from main.
Adapt the lesson example. Change one value or element, predict the result, and explain why it changes.
Review lesson →Open compiler
Show starting example
Go
```
package main
import "fmt"
func main() {
  name := "Ada"
  fmt.Println("Hello,", name)
}
```
2
Go Functions and Multiple Return Values
Return more than one value from a function.
Predict divide(20, 6).
Reveal answer and reasoning
It returns 3 and 2, so the output is 3 2.
Review lesson →Open compiler
Show starting example
Go
```
package main

import "fmt"

func divide(a, b int) (int, int) {
  return a / b, a % b
}

func main() {
  q, r := divide(17, 5)
  fmt.Println(q, r)
}
```
3
Go Loops
Count with the for statement.
Adapt the lesson example. Change one value or element, predict the result, and explain why it changes.
Review lesson →Open compiler
Show starting example
Go
```
package main
import "fmt"
func main() {
  for i := 1; i <= 3; i++ {
    fmt.Println(i)
  }
}
```
4
Go Structs and Methods
Group fields in a struct and attach behavior to it.
Add a Perimeter method.
Reveal answer and reasoning
func (r Rect) Perimeter() int { return 2 * (r.Width + r.Height) } returns 14 for this rectangle.
Review lesson →Open compiler
Show starting example
Go
```
package main

import "fmt"

type Rect struct {
  Width, Height int
}

func (r Rect) Area() int {
  return r.Width * r.Height
}

func main() {
  r := Rect{Width: 3, Height: 4}
  fmt.Println(r.Area())
}
```
5
Go Slices
Grow a sequence with append and take a part of it.
What does scores[:2] print for the final slice?
Reveal answer and reasoning
It runs from the start up to index 2, so it prints [82 91].
Review lesson →Open compiler
Show starting example
Go
```
package main

import "fmt"

func main() {
  scores := []int{82, 91, 76}
  scores = append(scores, 95)
  fmt.Println(len(scores), scores[3])
  fmt.Println(scores[1:3])
}
```

Go Basics

Go Functions and Multiple Return Values

Go Loops

Go Structs and Methods

Go Slices