RosettaCodeData/Task/Fractran/Go/fractran-2.go

36 lines
728 B
Go

package main
import (
"fmt"
"log"
"math/big"
"os"
"os/exec"
)
func main() {
c := exec.Command("ft", "1000000", "2", `17/91 78/85 19/51 23/38
29/33 77/29 95/23 77/19 1/17 11/13 13/11 15/14 15/2 55/1`)
c.Stderr = os.Stderr
r, err := c.StdoutPipe()
if err != nil {
log.Fatal(err)
}
if err = c.Start(); err != nil {
log.Fatal(err)
}
var n big.Int
for primes := 0; primes < 20; {
if _, err = fmt.Fscan(r, &n); err != nil {
log.Fatal(err)
}
l := n.BitLen() - 1
n.SetBit(&n, l, 0)
if n.BitLen() == 0 && l > 1 {
fmt.Printf("%d ", l)
primes++
}
}
fmt.Println()
}