1 编写程序，完成以下要求：

• 统计字符串中，各个字符的个数
• 比如："hello world" 字符串统计的结果为： h:1 e:1 l:3 o:2 d:1 r:1 w:1

•  print("-"*50)
  
   print("*"*50)
  
   currentstr = input("PLease input a sentence, the program will cal the word num:")
  
   currentstr=currentstr.replace(' ','')## Delete the 'Space' value
  
   newstr=''  #a new string to store the result
  
   for i in currentstr:
  
           if(currentstr.count(i)<=1):# if  there is only one word in currentstr
  
                   newstr=newstr+i
  
                   newstr=newstr+':'
  
                   newstr=newstr+str(1)+' '
  
           else:#the word has 2 or more numbers
  
                   if(newstr.count(i)<1): # has not register in the new string
  
                           newstr= newstr+i
  
                           newstr=newstr+':'
  
                           newstr= newstr+str(currentstr.count(i))+' '
  
   print("-"*50)
  
   print("The word number in this sentence is : %s"%newstr)
  
   print("-"*50)
  

结果如下：