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<algorithm>
#include<string>
#include<map>
#include<iomanip>
#include<vector>
#define rep(i,a,b) for(int i=a;i<b;i++)
using namespace std;
using ll = long long;
const int M = 100010;

int main() {
	string s1,s2;
	int c=0;

	while(1){
		cin>>s1;
		if(s1==".")break;
		cin>>s2;
		bool flag=false;	// " が奇数個目? y:true/n:false;
		c=0;	//" "の中が違う状態の数;
		int tmp1=0;	//s1の検索位置をずらして補正;
		int tmp2=0;	//s2の検索位置をずらして補正;
		for(int i=0;i+tmp1<s1.size()||i+tmp2<s2.size();i++){
			//" "の中以外で異なる文字があった場合;
			if(flag==false&&s1[i+tmp1]!=s2[i+tmp2]){
				cout<<"DIFFERENT"<<endl;
				flag=true;
				break;
			}
			//" "の中でs1とs2の文字が異なる場合;
			//tmp1,tmp2を使って個数を補正する;
			if(flag&&s1[i+tmp1]!=s2[i+tmp2]){
				c++;
				for(int j=0;;j++)
					if(s1[i+tmp1+j]=='"'){
						tmp1+=j;
						break;
					}
				for(int j=0;;j++){
					if(s2[i+tmp2+j]=='"'){
						tmp2+=j;
						break;
					}
				}
				//" "の中をスキップして、次は偶数個目の " の次の文字から探索;
				flag=false;
				continue;
			}
			//奇数個目の " が来た場合,flagを立てる;
			if(!flag&&s1[i+tmp1]=='"'){
				flag=true;
				continue;
			}
			//偶数個目の " が来た場合,flagを立てない;
			if(flag&&s2[i+tmp2]=='"')flag=false;
		}
		if(flag)continue;
		if(c==1)
			cout<<"CLOSE"<<endl;
		else if(c==0)
			cout<<"IDENTICAL"<<endl;
		else 
			cout<<"DIFFERENT"<<endl;
	}
	return 0;
}

C++: #include <iostream>
using namespace std;

int main(){
	while(1){
		string s1,s2;
		cin >> s1;
		if(s1==".")break;
		cin >> s2;

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

		string t1,t2;
		t1 = s1;t2 = s2;
		while(1){
			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;
			u2.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<string>
#include<utility>

using namespace std;

int main(){

  char s1[200]={};
  char s2[200]={};
  char t1[200]={};
  char t2[200]={};
char u1[200]={};
  char u2[200]={};

  int c=0,flag=0,j=0,k=0,l=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++;    
    }

    if(flag==0){
      u1[l]=s1[i];
      l++;    
    }


  }
  j=0;
  l=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++;
    }

 if(flag==0){
      u2[l]=s2[i];
      l++;
    }

  }
 j=0;
 flag=0;


   
  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;

    }


  }

  for(int i=0;i<200;i++){
    if(u1[i]!=u2[i]){
      c=2;
    }
  }

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