package main

import (
    "fmt"
    "math"
)

type Shape interface {
    area() float64
    perimeter() float64
}

type Circle struct {
    radius float64
    //Shape
}

type Rectangle struct {
    width, height float64
    //Shape
}

func (rectangle *Rectangle) area() float64 {
    return rectangle.width * rectangle.height
}

func (rectangle *Rectangle) perimeter() float64 {
    return 2 * (rectangle.width + rectangle.height)
}

func (circle *Circle) area() float64 {
    return math.Pi * math.Pow(circle.radius, 2)
}

func (circle *Circle) perimeter() float64 {
    return 2 * math.Pi * circle.radius
}

func main() {
    c := Circle{radius: 23}
    r := Rectangle{height: 11, width: 77.05}
    fmt.Printf("Circle's area is \t%f\nand perimeter is \t%f\n", c.area(), c.perimeter())
    fmt.Printf("Rectangle's area is \t%f\nand perimeter is \t%f\n", r.area(), r.perimeter())
}