07. Area of Figures

package main
import (
    "fmt"
    "math"
)

func main() {
    var figure string
    fmt.Scanln(&figure)

    var area = 0.0

    if (figure == "square") {
        var side float64
        fmt.Scanln(&side)
        area = side * side
    } else if (figure == "rectangle") {
            var base, height float64
            fmt.Scanln(&base)
            fmt.Scanln(&height)
            area = base * height
    } else if (figure == "circle") {
        var radius float64
            fmt.Scanln(&radius)
            area = math.Pi * radius * radius
    } else if (figure == "triangle") {
        var base, height float64
            fmt.Scanln(&base)
            fmt.Scanln(&height)
            area = base * height / 2
    }

    fmt.Println(area)
}