Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
)

func main() {
	io := NewIo()
	defer io.Flush()
	for {
		s := io.NextLine()
		if s == "." {
			break
		}
		t := io.NextLine()
		if s == t {
			io.Println("IDENTICAL")
			continue
		}
		ss := strings.Split(s, "\"")
		tt := strings.Split(t, "\"")
		if len(ss) != len(tt) {
			io.Println("DIFFERENT")
			continue
		}
		cnt := 0
		for i := 0; i < len(ss); i++ {
			if i%2 == 0 {
				if ss[i] != tt[i] {
					cnt = -1
					break
				}
			} else {
				if ss[i] != tt[i] {
					cnt++
				}
			}
		}
		if cnt > 1 || cnt == -1 {
			io.Println("DIFFERENT")
		} else {
			io.Println("CLOSE")
		}
	}
}

// I/O template
type Io struct {
	reader    *bufio.Reader
	writer    *bufio.Writer
	tokens    []string
	nextToken int
}

func NewIo() *Io {
	return &Io{
		reader: bufio.NewReader(os.Stdin),
		writer: bufio.NewWriter(os.Stdout),
	}
}

func (io *Io) Flush() {
	err := io.writer.Flush()
	if err != nil {
		panic(err)
	}
}

func (io *Io) NextLine() string {
	var buff []byte
	for {
		line, isPrefix, err := io.reader.ReadLine()
		if err != nil {
			panic(err)
		}
		buff = append(buff, line...)
		if !isPrefix {
			break
		}
	}
	return string(buff)
}

func (io *Io) Next() string {
	for io.nextToken >= len(io.tokens) {
		line := io.NextLine()
		io.tokens = strings.Fields(line)
		io.nextToken = 0
	}
	s := io.tokens[io.nextToken]
	io.nextToken++
	return s
}

func (io *Io) NextInt() int {
	i, err := strconv.Atoi(io.Next())
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) NextFloat() float64 {
	i, err := strconv.ParseFloat(io.Next(), 64)
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) Println(a ...interface{}) {
	fmt.Fprintln(io.writer, a...)
}

func (io *Io) Printf(format string, a ...interface{}) {
	fmt.Fprintf(io.writer, format, a...)
}

func (io *Io) PrintIntSlice(a []int) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func (io *Io) PrintStringSlice(a []string) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func Log(name string, value interface{}) {
	fmt.Fprintf(os.Stderr, "%s=%+v\n", name, value)
}

func ExampleIo() {
	io := NewIo()
	defer io.Flush()
	a := make([]int, 0, 3)
	a[0], a[1], a[2] = io.NextInt(), io.NextInt(), io.NextInt()
	io.Println(a)
	io.PrintIntSlice(a)
	Log("io", a)
}

C++: #include<iostream>
#include<vector>
#include<string>
using namespace std;
struct moji{
  string st;
  bool is_t;
};
void create_st(string& s,vector<moji>& sv){
    for(int i=0;i<s.size();i++){
      if(s[i]!='"') {
        string tmp(1,s[i]);
        moji add={tmp,false};
        sv.push_back(add);
      }else{
        string tmp="";
        int j=i+1;
        while(s[j]!='"'){
          tmp+=s[j];
          j++;
        }
        moji add={tmp,true};
        sv.push_back(add);
        i=j;
      }
    }
}
int main(){
  string s,t;
  cin >> s >> t;
  while(true){
    vector<moji> sv,tv;
    create_st(s,sv);
    create_st(t,tv);
    if(sv.size()!=tv.size()){
      cout <<"DIFFERENT\n";
    }else{
      int cnt=0;
      for(int i=0;i<sv.size();i++){
        if(sv[i].st!=tv[i].st){
          if(sv[i].is_t==false||tv[i].is_t==false)cnt+=2;
          else cnt++;
        }else if(sv[i].is_t!=tv[i].is_t) cnt+=2;
        if(cnt>=2) break;
      }
      if(cnt==0) cout <<"IDENTICAL\n";
      else if(cnt==1) cout <<"CLOSE\n";
      else cout <<"DIFFERENT\n";
    }
    cin>>s;
    if(s.size()==1&&s[0]=='.')break;
    cin >> t;
  }
}

C++: #include<iostream>
#include<string>
#include<utility>

using namespace std;

int main(){

  char s1[200]={0};
  char s2[200]={0};
  char t1[200]={0};
  char t2[200]={0};
  int c,flag=0,j=0,k=0;

  cin>>s1>>s2;
 
  for(int i=0;i<200;i++){
    if(s1[i]=='"'){
      if(flag==0){
	flag=1;
	
      }else if(flag==1){
	flag=0;
	
      }
    }

    if(flag==1){
      t1[j]=s1[i];
      j++;
      
    }

  }
  j=0;

 for(int i=0;i<200;i++){

    if(s2[i]=='"'){
      if(flag==0){
	flag=1;
	
      }else if(flag==1){
	flag=0;
	
      }
    }

    if(flag==1){
      t2[j]=s2[i];
      j++;
    }

  }
 j=0;
 flag=0;

  cout<<t1<<endl;
 cout<<t2<<endl;

 //kyuukei~~~

   
  for(int i=0;i<150;i++){


    if(flag==1){
    if(t1[j]!=t2[k]){
      c++;
      flag=0;
    }

    if(t1[j]=='"' && t2[k]!='"'){
      j--;
    }
    if(t2[k]=='"' && t1[j]!='"'){
      k--;
    }

    j++;
    k++;

    }

   if(t1[j]=='"' && t2[k]=='"'){
     flag=1;

    }



  

  }


    if(c==0){
      cout<<"IDENTICAL"<<endl;
    }else if(c==1){
      cout<<"CLOSE"<<endl;
    }else{
      cout<<"DIFFERENT"<<endl;
    }
  
return 0;
}

C++: #include<bits/stdc++.h>
using ll  = long long;
#define int ll
#define rep(i,n) for(int i=0;i<n;i++)
#define loop(i,s,n) for(int i=s;i<n;i++)
#define erep(e,v) for(auto && e :v)
#define all(in) in.begin(), in.end()
#define MP make_pair
#define INF (sizeof(int) == 4 ? (int)1e9:(int)1e18)
#define EPS 0.0000000001
using namespace std;
template<class T, class S> void cmin(T &a, const S &b) { if (a > b)a = b; }
template<class T, class S> void cmax(T &a, const S &b) { if (a < b)a = b; }
template<typename Head, typename Value> auto vectors(const Head &head, const Value &v) { return vector<Value>(head, v); }
template<typename Head, typename... Tail> auto vectors(Head x, Tail... tail) { auto inner = vectors(tail...); return vector<decltype(inner)>(x, inner); }
template<class T> void join(T a){for(auto itr :a){if(itr != *a.begin())cout << " "; cout << itr;} }
using ld  = long double;
using pii = pair<int,int>;
using piii = pair<int,pii>;
int W,H;
int dx[]={0,0,1,-1}, dy[]={1,-1,0,0};
bool valid(int x,int y){return (0<=x&&x<W)&&(0<=y&&y<H);}
using data = pair<string,bool>;
auto perse(string s){
    vector<data>sub;
    bool flag = false;
    string temp = "";
    for(auto c :s){
        if(c == '"' and flag == false){
            sub.push_back(make_pair(temp,false));
            temp.clear();
            flag = true;
        }else if(c == '"' and flag == true){
            sub.push_back(make_pair(temp,true));
            temp.clear();
            flag = false;
        } else temp.push_back(c);
    }
    if(temp.size())sub.push_back(make_pair(temp, false));
    return sub;
}
signed main(){
    string s,t;
    while(cin >> s){
        if(s == ".")break;
        cin >> t;
        if(s == t)cout << "IDENTICAL" << endl;
        else {
            auto sv = perse(s);
            auto tv = perse(t);
            if(tv.size() == sv.size()){
                int dif = 0;
                rep(i,tv.size()){
                    if(tv[i].first == sv[i].first and tv[i].second == sv[i].second){
                        //nothing to do
                    } else if(tv[i].first ==sv[i].first and tv[i].second != sv[i].second){
                        dif += 100;
                    } else if(tv[i].second == sv[i].second){
                        dif += (tv[i].second ? 1: 100);
                    }
                }
                cout << (dif == 1 ? "CLOSE" : "DIFFERENT") << endl;
            } else cout << "DIFFERENT" << endl;
        }
    }
}