test.go

package main

import (
	"crypto/sha256"
	"encoding/hex"
	"fmt"
)

func main() {
	right := "3187c721dc9913aef26a6cf1677a29a0c1c24229730911e68091eadf8839873"
	data := make([]byte, 64)
	right_bytes, _ := hex.DecodeString(right)
	copy(data[32:], right_bytes)

	hashed_with_empty_bytes := sha256.Sum256(data)
	fmt.Printf("with empty bytes: %s\n", hex.EncodeToString(hashed_with_empty_bytes[:]))

	hashed_without_empty_bytes := sha256.Sum256(right_bytes)
	fmt.Printf("without empty bytes: %s\n", hex.EncodeToString(hashed_without_empty_bytes[:]))
}