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>
#include<utility>

using namespace std;

int main(){

  char s1[200]={0};
  char s2[200]={0};
  char t1[200]={0};
  char t2[200]={0};
char u1[200]={0};
  char u2[200]={0};

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

  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;

 /* cout<<t1<<endl;
 cout<<t2<<endl;
 cout<<u1<<endl;
 cout<<u2<<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;

    }


  }

  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;
}

C++: #include <iostream>
#include <cstdio>
#include <algorithm>
using namespace std;
string qoo1[220],qoo2[220];
string nom1[220],nom2[220];

void pro(string qoo[],string nom[],string s,int &j,int &k){
    int len = s.length();
    bool ok = false,fg = false;
    for(int i=0; i<len; i++){
        if(ok==false&&s[i]!='\"'&&fg==false){
            fg = true;
            nom[++k]+=s[i];
            continue;
        }
        if(ok==false&&s[i]!='\"'&&fg){
            nom[k]+=s[i];
            continue;
        }
        if(ok==false&&s[i]=='\"'){
            ok = true;
            continue;
        }
        if(ok&&s[i]!='\"'){
            qoo[j]+=s[i];
            continue;
        }
        if(ok&&s[i]=='\"'){
            ok = false;
            fg = false;
            j++;
            continue;
        }
    }
    /*cout<<"qoo: "<<endl;
    for(int i=0; i<j; i++){
        cout<<qoo[i]<<" ";
    }cout<<endl;
    cout<<"nom: "<<endl;
    for(int i=0; i<=k; i++){
        cout<<nom[i]<<" ";
    }cout<<endl;*/

}
void ini(){
    for(int i=0; i<210; i++){
        qoo1[i] = "";
        qoo2[i] = "";
        nom1[i] = "";
        nom2[i] ="";
    }
}

int main(){
	string s1,s2;
	while(true){
        ini();
		cin>>s1;
		if(s1[0]=='.') break;
		cin>>s2;
		if(s1==s2){
			cout<<"IDENTICAL"<<endl;
			continue;
		}
		int len1 = s1.length(),len2 = s2.length();
		int j1=0,j2=0;
		int k1=-1,k2 =-1;
        pro(qoo1,nom1,s1,j1,k1);
        pro(qoo2,nom2,s2,j2,k2);
        if(k1!=k2||j1!=j2){
            cout<<"DIFFERENT"<<endl;
            continue;
        }
        bool ok = true;
        int cnt = 0;
        for(int i=0; i<j1; i++){
            if(qoo1[i]!=qoo2[i]) cnt++;
        }
        if(cnt>1){
            ok = false;
        }
        for(int i=0; i<=k1; i++){
            if(nom1[i]!=nom2[i]) ok = false;
        }
        if(ok){
            cout<<"CLOSE"<<endl;
            continue;
        }
        cout<<"DIFFERENT"<<endl;


	}
    return 0;
}

C++: #include<iostream>
#include<string>
using namespace std;
int main() {
	while (true) {
		string a, b;
		cin >> a;
		if (a == ".") {
			break;
		}
		cin >> b;
		if (a == b) {
			cout << "IDENTICAL" << endl;
			continue;
		}
		int modea = 0, modeb = 0;
		int i = 0, j = 0, k = 0, c = 0,l=0;
		a.append("\0");
		while(a[l]!=NULL){
			if (a[i+j] == '"') {
				switch(modea) {
					case 0:
						modea = 1;
						break;
					case 1:
						modea = 0;
						j=0;
						break;
				}
			}
			if (b[i+k] == '"') {
				switch(modeb) {
					case 0:
						modeb = 1;
						break;
					case 1:
						modeb = 0;
						k=0;
						break;
				}
			}
			if (modea == 1 and modeb==1) {
			  //  cout<<a[i+j]<<b[i+k]<<endl;
				if (a[i + j] != b[i + k]) {
					c++;
					break;
				}
				j++;
				k++;
			}
			else if (modea == 1) {
				j++;
			}
			else if(modeb==1){
				k++;
			}
			if(modea==0 or modeb==0){
				if (a[i] != b[i]) {
					c = c + 2;
					break;
				}
				
				i++;
			}
	cout<<a[i]<<b[i]<<c<<endl;
			l++;
		}
		if (c > 1) {
			cout << "DIFFERENT" << endl;
		}
		else {
			cout << "CLOSE" << endl;
		}
	}
}

C++: #include <bits/stdc++.h>

using namespace std;

int main(){
    while(true){
        string s,t;
        cin>>s;
        if(s==".")break;
        cin>>t;
        int si=0,ti=0;
        bool dq=false;
        int stat=0;//0:IDENTICAL 1:CLOSE 2:DIFFERENT
        while(si<s.size()&&ti<t.size()){
            if(dq){
                if(s[si]!=t[ti]){
                    ++stat;
                    while(s[si]!='"')++si;
                    while(t[ti]!='"')++ti;
                    dq=false;
                }
                if(s[si]=='"')dq=false;
            }
            else{
                if(s[si]!=t[ti]){
                    stat=2;
                    goto end;
                }
                else if(s[si]=='"')dq=true;
            }
            ++si;++ti;
        }
        end:;
        if(stat==0&&s.size()!=t.size())stat=2;
        switch(stat){
            case 0:
                cout<<"IDENTICAL"<<endl;
                break;
            case 1:
                cout<<"CLOSE"<<endl;
                break;
            default:
                cout<<"DIFFERENT"<<endl;
                break;
        }
    }
    return 0;
}