Является ли одна строка циклическим сдвигом другой?

#include <bits/stdc++.h>
 
using namespace std;
 
int main() {
    
    int res = 0, len; char tmp;
    string s1, s2;
    getline(cin,s1);
    getline(cin,s2);
 
    len = s1.size();
    
    while (s1 != s2) {
        tmp = s2[0];
        for (int i = 0; i < len - 1; i++)
            s2[i] = s2[i+1];
        s2[len-1] = tmp;
        res++;
        if (res == len) break;
    }
    if (res != len) cout << res << "\n";
    else cout << "-1" << "\n";
    
    return 0;
}

#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
 
using namespace std;
 
size_t if_sifted_str(const string &orig, const string &if_shifted) {
    
    if(orig == if_shifted) return 0 ;
    if(orig.size() != if_shifted.size()) return -1 ;
 
    auto orig_begin = orig.begin(), orig_end = orig.end()-1, if_shifted_begin = if_shifted.begin();
 
    string substring(orig, 0, orig.size()-1);
 
    while(orig_begin < orig_end) {
        auto pos_fnd = if_shifted.find(substring);
        if(pos_fnd != string::npos &&
           equal(if_shifted_begin, if_shifted_begin + pos_fnd, orig_end)){ //pos_fnd
            return pos_fnd ;
        }
        --orig_end ;
        substring.erase( substring.end()-1, substring.end()) ;
    }
    
    return -1;
}
 
 
 
int main() {
 
  string  orig, s;
  getline(cin, orig);
  getline(cin, s);
  vector<string> words;
  words.push_back(s);
 
for (const auto &str:words) {
    size_t shift_dist(-1);
    if ((shift_dist = if_sifted_str(orig, str)) != -1) {
        if ((shift_dist) != 0) cout << shift_dist << endl; else
            cout << shift_dist + s.length();
    }    
    else
        cout << -1 << endl;
}
 
return 0;
}

#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
 
using namespace std;
 
size_t if_sifted_str(const string &orig, const string &if_shifted) {
    
    if(orig == if_shifted) return 0 ;
    if(orig.size() != if_shifted.size()) return -1 ;
 
    auto orig_begin = orig.begin(), orig_end = orig.end()-1, if_shifted_begin = if_shifted.begin();
 
    string substring(orig, 0, orig.size()-1);
 
    while(orig_begin < orig_end) {
        auto pos_fnd = if_shifted.find(substring);
        if(pos_fnd != string::npos &&
           equal(if_shifted_begin, if_shifted_begin + pos_fnd, orig_end)){ //pos_fnd
            return pos_fnd ;
        }
        --orig_end ;
        substring.erase( substring.end()-1, substring.end()) ;
    }
    
    return -1;
}
 
 
 
int main() {
 
  string  orig, s;
  getline(cin, orig);
  getline(cin, s);
  vector<string> words;
  words.push_back(s);
 
for (const auto &str:words) {
    size_t shift_dist(-1);
    if ((shift_dist = if_sifted_str(orig, str)) != -1)
        cout << shift_dist << endl;
    else
        cout << -1 << endl;
}
 
return 0;
}

string substring(orig, 0, orig.size()-1);

--orig_end ;
        substring.erase( substring.end()-1, substring.end()) ;////////////////////тута
    }
    
    return -1;
}

if_sifted_str("axx", "xab")

size_t if_sifted_str(const string &orig, const string &if_shifted)
{
    if(orig == if_shifted) return 0 ;
    if(orig.size() != if_shifted.size()) return -1 ;
 
    auto orig_begin =
    orig.begin(), orig_end =orig.end()-1, if_shifted_begin = if_shifted.begin() ;
 
    string substring(orig, 0, orig.size()-1);
 
    while(orig_begin<orig_end)
    {
 
        auto pos_fnd=if_shifted.find(substring);
 
         if(pos_fnd !=string::npos && 
        pos_fnd+substring.size()==if_shifted.size() && //доп условие
           equal(
                 if_shifted_begin, if_shifted_begin+pos_fnd,
                 orig_end) ){
            return pos_fnd ;
        }
        --orig_end ;
        substring.erase( substring.end()-1, substring.end()) ;
    }
 return -1;
}

size_t if_shifted_str(const string &orig, const string &if_shifted) 
{
  size_t n = orig.length();
  if (if_shifted.length() != n)
    return -1;
 
  for (size_t i = 0; i < n; ++i)
    if (string_view(if_shifted).substr(0, i) == string_view(orig).substr(n - i) &&
        string_view(if_shifted).substr(i) == string_view(orig).substr(0, n - i))
      return i;
 
  return -1;
}

size_t if_shifted_string(const string &orig, const string &if_shifted)
{
    size_t len= orig.size();
    if(orig == if_shifted) return 0 ;
    if(len != if_shifted.size()) return -1 ;
 
    auto orig_begin = orig.begin()+1, orig_end =orig.end(),
         if_shifted_begin = if_shifted.begin(), if_shifted_end = if_shifted.end() ;
 
      for(auto broken_orig_begin= orig_begin; broken_orig_begin!=orig_end; ++broken_orig_begin )
      {
         size_t shift =if_shifted.size()-(broken_orig_begin-orig.begin());
 
         if(    equal(broken_orig_begin, orig_end, if_shifted_begin) &&
                equal(if_shifted_begin+shift, if_shifted_end,  orig.begin())    )   return shift ;         
      }
     return -1;
}

template<class Container>
size_t if_shifted_sequence(const Container &orig, const Container &if_shifted)
{
    size_t len= orig.size();
    if(orig == if_shifted) return 0 ;
    if(len != if_shifted.size()) return -1 ;
 
    auto orig_begin = ++begin(orig), orig_end = end(orig),
         if_shifted_begin = begin(if_shifted), if_shifted_end = end(if_shifted) ;
         size_t sycles(0);
      for(auto broken_orig_begin= orig_begin; broken_orig_begin!=orig_end; ++broken_orig_begin )
      {
         size_t shift =len-++sycles;
 
         auto if_shifted_begin_to_shift=if_shifted_begin;
         advance(if_shifted_begin_to_shift, shift) ;
 
         if(    equal(broken_orig_begin, orig_end, if_shifted_begin) &&
                equal(if_shifted_begin_to_shift, if_shifted_end,  --orig_begin)    )   return shift ;
      }
     return -1;
}
 
 
template<class RndIt>
size_t if_shifted_sequence( RndIt orig_begin, RndIt orig_end,  RndIt if_shifted_begin)
{
    if(    equal(orig_begin, orig_end, if_shifted_begin) ) return 0;
    size_t len= orig_end-orig_begin ;
 
    auto if_shifted_end =if_shifted_begin+len ;
         size_t sycles(0);
 
      for(auto broken_orig_begin= ++orig_begin;//сначала уже проверено на входе в функцию
       broken_orig_begin!=orig_end; ++broken_orig_begin )
      {
         size_t shift =len-++sycles;
 
         auto if_shifted_begin_to_shift=if_shifted_begin;
         advance(if_shifted_begin_to_shift, shift) ;
 
         if(    equal(broken_orig_begin, orig_end, if_shifted_begin) &&
                equal(if_shifted_begin_to_shift, if_shifted_end,  --orig_begin)    )   return shift ;
      }
     return -1;
}
 
template <typename Container>
void prn(const Container &container)
{
    for(const auto &el:container)
    {
        cout<<el;
    }
}
 
int main()
{
 vector<int>orig{1,2,3,4,5};
 string  orig1 =
   "something"
  //"axx"
  ;
  //string words1[]=
  vector<string> words1{"something", "gsomething", "gsomethin", "omethings", "thingsome", "theingsom", "methingso"
     //"xab"
  } ;
 
  vector<vector<int>> words
  {
      {1,2,3,4,5},
      {2,3,4,5,1},
      {3,4,5,1,2},
      {2,4,3,5,1},
      {1,2,2,1,2}
       
  } ;
  
for(auto &str:words)
{
    size_t shift_dist(-1);
  // if( (shift_dist=if_shifted_sequence(orig, str) ) != -1 ){
     if( (shift_dist= if_shifted_sequence(orig.begin(), orig.end(), str.begin()) ) != -1 ){
    prn(str);
    cout<< " is shifted ";
    prn(orig);
    cout <<" by "<< shift_dist <<endl;
    }
    else{
        prn(str);
        cout<< " is Not shifted ";
         prn(orig);
        cout<<endl;
 
    }
        cout<<"\n------------\n";
}
 
cout<<"\n\n______string_________\n";
for(const auto &str:words1)
{
    size_t shift_dist(-1);
    if( (shift_dist=if_shifted_sequence(orig1, str) ) != -1 )
    cout<<str<< " is shifted "<<orig1 <<" by "<< shift_dist <<endl;
    else
        cout<<str<< " is Not shifted "<<orig1 <<endl;
        cout<<"\n------------\n";
}
 
return 0;
}