Solution: rectangular CLI

---

examples/rectangular/rectangular.go

package main

import (
    "fmt"
    "os"
    "strconv"
)

func main() {
    var err error
    var width int
    var height int

    if len(os.Args) != 3 {
        fmt.Printf("Usage: %v WIDTH HEIGHT\n", os.Args[0])
        os.Exit(1)
    }

    width, err = strconv.Atoi(os.Args[1])
    if err != nil {
        fmt.Println(err)
        os.Exit(1)
    }

    height, err = strconv.Atoi(os.Args[2])
    if err != nil {
        fmt.Println(err)
        os.Exit(1)
    }

    fmt.Println(width)
    fmt.Println(height)

    area := width * height
    fmt.Printf("The area of the rectangular is: %v\n", area)
}