题解 | 年轻人不讲5的

package main

import (
	"bufio"
	"fmt"
	"os"
)

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Buffer(make([]byte, 1024*1024), 1024*1024)
	sc.Scan()
	b := sc.Bytes()
	for i, e := range b {
		if e == '5' {
			b[i] = '*'
		}
	}
	fmt.Print(string(b))
}