make same performance improvements to all sieve commands

cmd/divisors.go

@@ -17,7 +17,9 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
 package cmd
 
 import (
+	"bufio"
 	"fmt"
+	"os"
 
 	"github.com/spf13/cobra"
 	"scm.dairydemon.net/filifa/mathtools/internal/lib"
@@ -27,7 +29,10 @@ var divisorsN uint
 var divisorsE uint
 
 func divisors(cmd *cobra.Command, args []string) {
-	ch := lib.DivisorsSieve(divisorsN, divisorsE)
+	bufStdout := bufio.NewWriter(os.Stdout)
+	defer bufStdout.Flush()
+
+	ch := lib.DivisorsSieve(divisorsN, divisorsE, 1000)
 	for i := 0; ; i++ {
 		v, ok := <-ch
 		if !ok {
@@ -38,7 +43,7 @@ func divisors(cmd *cobra.Command, args []string) {
 			continue
 		}
 
-		fmt.Println(v)
+		fmt.Fprintln(bufStdout, v)
 	}
 }
 

cmd/mobius.go

@@ -17,7 +17,9 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
 package cmd
 
 import (
+	"bufio"
 	"fmt"
+	"os"
 
 	"github.com/spf13/cobra"
 	"scm.dairydemon.net/filifa/mathtools/internal/lib"
@@ -26,7 +28,10 @@ import (
 var mobiusN uint
 
 func mobius(cmd *cobra.Command, args []string) {
-	ch := lib.MobiusSieve(mobiusN)
+	bufStdout := bufio.NewWriter(os.Stdout)
+	defer bufStdout.Flush()
+
+	ch := lib.MobiusSieve(mobiusN, 1000)
 	for i := 0; ; i++ {
 		v, ok := <-ch
 		if !ok {
@@ -37,7 +42,7 @@ func mobius(cmd *cobra.Command, args []string) {
 			continue
 		}
 
-		fmt.Println(v)
+		fmt.Fprintln(bufStdout, v)
 	}
 }
 

cmd/primeOmega.go

@@ -17,7 +17,9 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
 package cmd
 
 import (
+	"bufio"
 	"fmt"
+	"os"
 
 	"github.com/spf13/cobra"
 	"scm.dairydemon.net/filifa/mathtools/internal/lib"
@@ -27,7 +29,10 @@ var primeOmegaN uint
 var primeOmegaMul bool
 
 func primeOmega(cmd *cobra.Command, args []string) {
-	ch := lib.PrimeOmegaSieve(primeOmegaN, primeOmegaMul)
+	bufStdout := bufio.NewWriter(os.Stdout)
+	defer bufStdout.Flush()
+
+	ch := lib.PrimeOmegaSieve(primeOmegaN, primeOmegaMul, 1000)
 	for i := 0; ; i++ {
 		v, ok := <-ch
 		if !ok {
@@ -38,7 +43,7 @@ func primeOmega(cmd *cobra.Command, args []string) {
 			continue
 		}
 
-		fmt.Println(v)
+		fmt.Fprintln(bufStdout, v)
 	}
 }