go语言练习：sha256、sha512哈希算法

package main

import (
   "fmt"
   "crypto/sha256"
)

func main()  {
   str:="test hash..."
   s_ob:=sha256.New()
   s_ob.Write([]byte(str))
   r:=s_ob.Sum(nil)
   fmt.Printf("%x\n",r)
}

//sha256:     59039ef3b6f6ab469c357616b365b4b59a28c32d8ee880160ec793d1d543fc8d7474ffcf52f55532f49f6c627cbf0c3d10cc10b6704a793d11bb6800b09916cc
//sha256: