Simple Go code for https://shallenge.quirino.net/

main.go

package main

import (
	"crypto/sha256"
	"encoding/hex"
	"fmt"
	"math"
	"runtime"
	"sync"
	"sync/atomic"
)

var name = "boyter/"
var zeroCount int = 0
var mutex = sync.Mutex{}
var semaphore = make(chan bool, runtime.NumCPU())
var totalHashCount int64

func main() {
	jumpSize := int64(10_000_000)
	for i := int64(0); i < math.MaxInt64; i += jumpSize {
		semaphore <- true
		go func(i int64) {
			HashEm(i, i+jumpSize)
			<-semaphore
		}(i)
	}
}

func HashEm(start, end int64) {
	hash := sha256.New()
	for i := start; i <= end; i++ {
		atomic.AddInt64(&totalHashCount, 1)
		hash.Reset()
		hash.Write([]byte(fmt.Sprintf("%s%d", name, i)))
		sum := hash.Sum(nil)
		h := hex.EncodeToString(sum)

		zc := HashZeroCount(h)
		mutex.Lock()
		if zc != 0 && zc >= zeroCount {
			zeroCount = zc
			fmt.Println(fmt.Sprintf("%s%d", name, i), h, zeroCount)
		}
		mutex.Unlock()
	}
}

const zeroByte = 48

func HashZeroCount(hash string) int {
	zCount := 0
	for _, ch := range hash {
		if ch != zeroByte {
			return zCount
		}
		zCount++
	}

	return zCount
}