gen star

main.go

/*
     *
    ***
   *****
  *******
 *********
***********
 *********
  *******
   *****
    ***
     *

*/
package main

import (
	"fmt"
)

func replaceStr(ch string, n int) string{
	txt := ""
	for i:=0; i<n;i++{txt+=ch}
	return txt
}
func genLevel(level int) string{
	txt := ""
	ch := " "
	star := "*"
	for i:=0; i< (level*2)+1; i++{
		if i < level{
			txt += replaceStr(ch, level - i)+replaceStr(star, (i*2)+1) +"\n"
		}else{
			txt += replaceStr(ch, i-level)+replaceStr(star, (level*2)-((i-level)*2) +1) +"\n"
		}		
	}
	return txt
}

func main() {
	fmt.Println(genLevel(5))
}