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 <vector>
#include <list>
#include <map>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <queue>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <fstream>
#include <cstdio>
#include <climits>
#include <complex>
#include <cstdint>
#include <tuple>

#define M_PI       3.14159265358979323846

using namespace std;

//conversion
//------------------------------------------
inline int toInt(string s) { int v; istringstream sin(s); sin >> v; return v; }
template<class T> inline string toString(T x) { ostringstream sout; sout << x; return sout.str(); }
inline int readInt() { int x; scanf("%d", &x); return x; }

//typedef
//------------------------------------------
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef pair<int, PII> TIII;
typedef long long LL;
typedef unsigned long long ULL;
typedef vector<LL> VLL;
typedef vector<VLL> VVLL;

//container util

//------------------------------------------
#define ALL(a)  (a).begin(),(a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define SQ(a) ((a)*(a))
#define EACH(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i)
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define SORT(c) sort((c).begin(),(c).end())

//repetition
//------------------------------------------
#define FOR(i,s,n) for(int i=s;i<(int)n;++i)
#define REP(i,n) FOR(i,0,n)
#define MOD 1000000007

#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define trav(a, x) for(auto& a : x)
#define all(x) x.begin(), x.end()
#define sz(x) (int)(x).size()
struct Edge {
    int to, cost;
    Edge(int to, int cost): to(to), cost(cost) {}
};

typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<vector<Edge>> AdjList;
AdjList graph;

const int INF = 100000000;



int GCD(int a, int b){
    if(a < b) swap(a, b);
    if(b == 0) return a;
    return GCD(b, a%b);
}


void solve(){

}
int main() {
    //cout << fixed << setprecision(15);

    string s, t;
    while(cin >> s){
        if(s==".") break;
        cin >> t;

        vector<string> v1;
        vector<string> ababa1;

        int n = s.size();
        string news="";
        string tmp="";
        bool c = false;
        for(int i=0; i<n; ++i){

            if(s[i]=='"'){
                if(c==false){
                    c = true;
                    ababa1.push_back(news);
                    news = "";
                }
                else {
                    v1.push_back(tmp);
                    tmp = "";
                    c = false;
                }
            }
            if(s[i]!='"' && c == true){
                tmp += s[i];
            }
            else if(s[i] != '"' && c == false){
                news += s[i];
            }
        }

        if(news!="") ababa1.push_back(news);

        vector<string> v2;
        vector<string> ababa2;
        int m = t.size();
        string newt="";
        tmp ="";
        c = false;
        for(int i=0; i<m; ++i){

            if(t[i]=='"'){
                if(c==false) {
                    ababa2.push_back(newt);
                    newt="";
                    c = true;
                }
                else {
                    v2.push_back(tmp);
                    tmp = "";
                    c = false;
                }
            }
            if(t[i]!='"' && c == true){
                tmp += t[i];
            }
            else if(t[i] != '"' && c == false){
                newt += t[i];
            }
        }
        if(newt!="") ababa2.push_back(newt);

        if(ababa1.size()!=ababa2.size()){
            cout << "DIFFERENT" << endl;
        }else{
            bool jud = true;
            for(int i=0; i<ababa1.size(); ++i){
                if(ababa1[i] != ababa2[i]) jud = false;
            }
            if(!jud){
                cout << "DIFFERENT" << endl;
            }else{
                if(v1.size() != v2.size()){
                    cout << "DIFFERENT" << endl;
                }else{
                    int cnt=0;
                    for(int i=0; i<v1.size(); ++i){
                        if(v1[i]!=v2[i]) cnt++;
                    }
                    if(cnt==0) cout << "IDENTICAL" << endl;
                    else if(cnt==1) cout << "CLOSE" << endl;
                    else cout << "DIFFERENT" << endl;
                }
            }
        }
    }
    return 0;
}