monte_pi.go

// Calculates Pi using Monte Carlo. See http://montepie.herokuapp.com/
package main

import (
	"fmt"
	"math"
	"math/rand"
	"time"
)

func main() {
	rand.Seed(time.Now().Unix())
	n := 10000
	in := 0

	for i := 0; i < n; i++ {
		x := rand.Float64()
		y := rand.Float64()
		d := math.Sqrt(x*x + y*y)
		if d <= 1 {
			in++
		}
	}
	pi := 4.0 * float64(in) / float64(n)
	fmt.Println(pi)
}