sqrt.go

package main

import "fmt"

func abs(x float64) float64 {
    if x > 0 {
        return x
    } else {
        return -x
    }
}

func Sqrt(x float64) float64 {
    z := 1.0
    
    for abs(x - z*z) > 0.000001 {
    	z = z-(z*z-x)/(2*z)
    }
    return z
}

func main() {
    fmt.Println(Sqrt(9.0))
}