#include <bits/stdc++.h>
using namespace std;

string destuff(string s,string flag,int one)
{
    string ans="";
    int n=s.size();
    for(int i=0;i<n;i++)
    {
        if(s[i]=='1')
        {
            int count=0;
            for(;i<n&&s[i]=='1';i++)
            {
                ans.push_back('1');
                count++;
                if(count==one-1)
                {
                    i++;
                    count=0;
                }
            }
            i--;
        }
        else
        {
            ans.push_back('0');
        }
    }
    return ans;
}


string stuff(string s,string flag,int one)
{
    string ans=flag;
    int n=s.size();
    for(int i=0;i<n;i++)
    {
        if(s[i]=='1')
        {
            int count=0;
            for(;i<n&&s[i]=='1';i++)
            {
                ans.push_back('1');
                count++;
                if(count==one-1)
                {
                    ans.push_back('0');
                }
            }
            i--;
        }
        else
        {
            ans.push_back('0');
        }
    }
    ans.append(flag);
    return ans;
    
}

int main() {
   
    string s,s1,s2,flag;
    cout<<"Enter the string"<<endl;
    cin>>s;
    cout<<"Enter the delimiter"<<endl;
    cin>>flag;
    int one=0;
    for(auto c:flag)
    {
        if(c=='1')
        {
            one++;
        }
    }
    s1=stuff(s,flag,one);
    cout<<"after stuffing :"<<s1<<endl;
    s2=destuff(s,flag,one);
    cout<<"after destuffing: "<<s2<<endl;
    return 0;
}