题解 | #表示数字#

最笨的办法，一个个遍历，遇到 数字+字符 或者 字符+数字的情况就加 '*'，特别情况就是第一个是数字需要在前面加 '*'

while 1:
    try:
        s = input()
        tmp = ''
        if len(s)==1:
            tmp = '*'+s+'*' if 47<=ord(s)<=58 else s
        else:
            for i in range(len(s)):    
                if i==0 and 47<=ord(s[i])<=58:
                        tmp="*"            
                if i+1 <= len(s)-1:                   
                    if (ord(s[i])<47 or ord(s[i])>58) and 47<=ord(s[i+1])<=58:
                        tmp=tmp+s[i]+'*'
                    elif 47<=ord(s[i])<=58 and 47<=ord(s[i+1])<=58:
                        tmp+=s[i]
                    elif 47<=ord(s[i])<=58 and (ord(s[i+1])<47 or ord(s[i+1])>58):
                        tmp=tmp+s[i]+"*"
                    else:
                        tmp+=s[i]
                else:
                    tmp= tmp+s[i]+"*" if 47<=ord(s[i])<=58 else tmp+s[i]
        print(tmp)
    except:
        break