Answer:
here is code in C++.
#include <bits/stdc++.h>
using namespace std;
// function to alphabetize the input string
void alphabetize(string &str)
{
// find the length of string
  int n=str.size();
  
   for(int x=0;x<n;x++){
       for(int y=x+1;y<n;y++)
       {   
           //swap the character
           if(str[x]>str[y]){
               char ch=str[x];
               str[x]=str[y];
               str[y]=ch;
           }
       }
   }
  
   cout<<"alphabetize string is: "<<str<<endl;;
  
}
int main()
{// string variable to read input
   string inp;
  
   cout<<"Please Enter a String in lowercase :";
   //reading the input
   cin>>inp;
   // call function with inp argument
   alphabetize(inp);
   return 0;
   }
Explanation:
Declare a variable "inp" of string type and assign the input string to it. call the alphabetize() function with argument "inp".In the alphabetize(),find the length  of input string.Then travers the string and if a character is greater than any  next character in the string then swap it, so that all the character are sorted.
Output:
Please Enter a String in lowercase :helloworld                                                                                                                 
alphabetize string is: dehllloorw