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 <string>
using namespace std;


int main(){

	while(true){
		string s1;
		cin>>s1;

		if(s1==".")
			break;
		string s2;
		cin>>s2;

		if(s1==s2){
			cout<<"IDENTICAL"<<endl;
			continue;
		}

		string t1=s1;
		string t2=s2;

		while(true){

			size_t d1b =t1.find('\"');
			if(d1b==string::npos)
				break;
			t1.replace(d1b,1,"@");

			size_t d1e =t1.find('\"');
			t1.replace(d1e,1,"@");

			size_t d2b =t2.find('\"');
			if(d2b==string::npos)
				break;
			t2.replace(d2b,1,"@");

			size_t d2e =t2.find('\"');
			t2.replace(d2e,1,"@");

			string u1=s1;
			u1.replace(d1b+1,d1e-d1b-1,"");

			string u2=s2;
			u1.replace(d2b+1,d2e-d2b-1,"");

			if(u1==u2){
				t1=u1;
				t2=u2;
				break;
			}
		}

		if(t1==t2){
			cout<<"CLOSE"<<endl;
		}else{
			cout<<"DIFFERENT"<<endl;
		}
	}
	return 0;
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#include<iomanip>
#include<stack>
#include<queue>
#include<string>
#include<set>
#include<map>
#include<cmath>
#include<cstring>
using namespace std;

void read(string s,vector<string> &other,vector<string> &str){
    int state = 0;
    string now = "";
    for(int i=0;i<s.size();i++){
        if(s[i]=='"'){
            if(state==0){
                other.push_back(now);
            }else{
                str.push_back(now);
            }
            state = 1-state;
            now = "";
        }else{
            now+=s[i];
        }
    }
    if(state==0){
                other.push_back(now);
            }else{
                str.push_back(now);
            }
}

void deb(vector<string> v){
    for(int i=0;i<v.size();i++){
        cout << v[i];
        if(i!=v.size()-1)cout << " , ";
    }
    cout << endl;
}

int main(){
    string s1,s2;
    while(cin >> s1,s1!="."){
        cin >> s2;
        vector<string> other1,other2;
        vector<string> str1,str2;
        read(s1,other1,str1);
        read(s2,other2,str2);

        // deb(other1);
        // deb(other2);
        // deb(str1);
        // deb(str2);

        if(other1.size()!=other2.size()||str1.size()!=str2.size()){
            cout << "DIFFERENT" << endl;
            continue;
        }
        int state = 2;
        for(int i=0;i<other1.size();i++){
            if(other1[i]!=other2[i])state = 0;
        }
        int cnt = 0;
        for(int i=0;i<str1.size();i++){
            if(str1[i]!=str2[i]){
                if(state==2){
                    state=1;
                }else if(state==1){
                    state=0;
                }
            }
        }
        if(state==2){
            cout << "IDENTICAL" << endl;
        }else if(state==1){
            cout << "CLOSE" << endl;
        }else{
            cout << "DIFFERENT" << endl;
        }
    }
    return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<vector>

using namespace std;
int main()
{
  int start,end;
  string s1,s2;
  while(1){
    
    cin>>s1;
    if(s1==".") return 0;
    cin>>s2;
    vector<string> i1(0);
    vector<string> i2(0);
    //s1
    start=0,end=-1;
    for(int i=0;i<s1.size();i++){
      if(s1[i]=='"'){
	end=max(0,i-1);
	if(end-start>0){
	  //cout<<"a:i:"<<i<<" "<<s1.substr(start,end-start+1)<<" "<<endl;
	  i1.push_back(s1.substr(start,end-start+1));
	}else{
	  //cout<<"c:i:"<<i<<endl;
	  i1.push_back("");
	}
	start=i+1; end=-1;
	//cout<<"start:"<<start<<" end:"<<end<<endl;
      }
      if((end==-1)and(i==s1.size()-1)){
	end=i;
	//cout<<"b:i:"<<i<<" "<<s1.substr(start,end-start+1)<<" "<<endl;
	i1.push_back(s1.substr(start,end-start+1));
	start=i+1; end=-1;
      }
    }
    //s2
    start=0,end=-1;
    for(int i=0;i<s2.size();i++){
      if(s2[i]=='"'){
	end=max(0,i-1);
	if(end-start>0){
	  i2.push_back(s2.substr(start,end-start+1));
	}else{
	  i2.push_back("");
	}
	start=i+1; end=-1;
      } 
      if((end==-1)and(i==s2.size()-1)){
	end=i;
	i2.push_back(s2.substr(start,end-start+1));
	start=i+1; end=-1;
      }
    }
    int count=0;
    if(i1.size()!=i2.size()){
      //cout<<"a"<<endl;
      count=2;
    }else{
      for(int i=0;i<i1.size();i++){
	if(i%2){
	  if(i1[i]!=i2[i]){
	    //cout<<"b"<<endl;
	    count++;
	  }
	}else{
	  //cout<<"c"<<endl;
	  if(i1[i]!=i2[i]){
	    count=2;
	    break;
	  }
	}
      }
    }

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