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 <bits/stdc++.h>

#define REP(i, n) for (int i = 0; i < n; i++)
#define ALL(obj) obj.begin(), obj.end()
#define fcout cout << setprecision(10)

const int iINF = 1e9;
const long long llINF = 1e18;
const int MOD = 1e9 + 7;

using namespace std;

template <typename T>
void debug(vector<T> &vec) {
    for (auto x : vec) {
        cout << x << " ";
    }
    cout << endl;
    return;
}

template <typename A, size_t N, typename T>
void FILL(A (&array)[N], const T &val) {
    std::fill((T *)array, (T *)(array + N), val);
}

template <typename T>
int getFormer(const vector<T> &vec, T x) {
    return upper_bound(vec.begin(), vec.end(), x) - vec.begin() - 1;
}

template <typename T>
int getLatter(const vector<T> &vec, T x) {
    return lower_bound(vec.begin(), vec.end(), x) - vec.begin();
}

vector<string> split(string &s, char deli) {
    vector<string> res;
    string str = "";
    for (auto c : s) {
        if (c == deli) {
            if (res.size() % 2 == 0) {
                res.push_back(str);
            } else {
                str = '"' + str + '"';
                res.push_back(str);
            }

            str.clear();
        } else {
            str.push_back(c);
        }
    }

    if (!str.empty()) res.push_back(str);
    return res;
}

void solve(string s1, string s2) {
    int n = s1.size(), m = s2.size();
    vector<string> vars1, var2, syns1, syns2;
    vector<string> res1 = split(s1, '"'), res2 = split(s2, '"');
    bool isVars = res1[0][0] == '"' ? true : false;
    int diff = 0;
    if (res1.size() != res2.size()) {
        cout << "DIFFERENT" << endl;
        return;
    }

    for (int i = 0; i < res1.size(); i++) {
        if (isVars == true) {
            if (i % 2 == 0) {
                if (res1[i] == res2[i]) continue;
                diff += 1;
            } else {
                if (res1[i] != res2[i]) {
                    cout << "DIFFERENT" << endl;
                    return;
                }
            }
        } else {
            if (i % 2 == 1) {
                if (res1[i] == res2[i]) continue;
                diff += 1;
            } else {
                if (res1[i] != res2[i]) {
                    cout << "DIFFERENT" << endl;
                    return;
                }
            }
        }
    }

    if (diff == 0) {
        cout << "IDENTICAL" << endl;
    } else {
        cout << (diff == 1 ? "CLOSE" : "DIFFERENT") << endl;
    }
}

int main() {
    string s1, s2;
    while (cin >> s1 && s1 != ".") {
        cin >> s2;
        solve(s1, s2);
    }
    return 0;
}

C++: #include<iostream>
#include<vector>
#include<string>
int main(){
	int i,j,k,l,m,lim,flag1=0,flag2,flag3,flag4,count=0,x,scou1=0,scou2=0;
	std::string s1;
	std::string s2;
	std::vector<std::string> ans;
	char str1[200],str2[200];
	while(1){
		gets(str1);
		i=0;
		while(str1[i]!=NULL){
			s1.push_back(str1[i]);
			i++;
		}
//		std::cout<<s1<<"\n";
		if(s1=="."){
//			std::cout<<s1<<"\n";
			break;
		}
		gets(str2);
		k=0;
		while(str2[k]!=NULL){
			s2.push_back(str2[k]);
			k++;
		}
//		std::cout<<s2<<"\n";
//		std::cout<<i<<"\n";
		scou1=0;
		scou2=0;
		flag1=0;
		flag2=0;
		flag3=0;
		flag4=0;
		if(i<k){
			l=i;
			lim=k;
		}else{
			l=k;
			lim=i;
		}
		j=0;
		m=0;
		for(int z=0;z<l;z++){
			if(s1[j]=='"'){
				scou1++;
			}
			if(s2[m]=='"'){
				scou2++;
			}
			
			std::cout<<s1[j]<<" "<<s2[m]<<"\n";
			
			if(s1[j]!=s2[m]){
				if(flag4==1){
					flag2=1;
					break;
				}
				if(scou1%2==1&&scou2%2==1){
					flag2=2;
					flag3=1;
				}else if(scou1%2==1){
					while(s1[j]!='"'){
						j++;
					}
					scou1++;
					flag2=2;
					flag3=1;
				}else if(scou2%2==1){
					while(s2[m]!='"'){
						m++;
					}
					scou2++;
					flag2=2;
					flag3=1;
				}else{
					flag2=1;
					break;
				}
				
			}
			
			if(flag3==1&&scou1%2==0&&scou2%2==0){
					flag4=1;
					std::cout<<"tutgihanai\n";
				}
			
			j++;
			m++;
		}
		
		if(m<lim&&j<lim){
			flag2=1;
		}
		
//		std::cout<<m<<j<<lim<<"\n";
		
		if(flag2==0){
			ans.push_back("IDENTICAL");
		}else if(flag2==1){
			ans.push_back("DEFFERENT");
		}else{
			ans.push_back("CLOSE");
		}
		std::cout<<ans[count]<<"\n";
		
		count++;
		s1.erase(s1.begin(),s1.end());
		s2.erase(s2.begin(),s2.end());
	}
	
	for(int j=0;j<count;j++){
		std::cout<<ans[j]<<"\n";
	}
	
	return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<numeric>
#include<vector>
#include<set>
#include <math.h>
#include <string>
#define cinf(n,x,y) for(int i=0;i<(n);i++) cin >> x[i]>>y[i];
typedef long long int ll;
const ll INF =1LL << 62;
using namespace std;
int MAX_E=1000010;
ll dp[1000010];
void split(string s, vector<string> &v){
	v.clear();
	s +='"';
	string str="";
	for(int i=0;i<s.size();i++){
		if(s[i]=='"'){
			v.push_back(str);
			str="";
		}
		else{
			str+=s[i];
		}
	}
}
int main(){
	while(1){
		string s1,s2; cin >>s1;
		if(s1==".")break;
		cin >> s2;
		if(s1==s2){
			cout << "IDENTICAL"<< endl;
		}
		else{
			vector<string> v1,v2;
			split(s1,v1);
			split(s2,v2);
			if(v1.size()!=v2.size()){
				cout << "DIFFERENT" << endl;
			}
			else{
				bool a=false;
				int cnt=0;
				for(int i=0;i<v1.size();i++){
					if(i%2==0){
						if(v1[i]!=v2[i])a=true;
					}
					else{
						if(v1[i]!=v2[i])cnt++;
					}
				}
				if(a){
					cout << "DIFFERENT" << endl;
				}
				else if(cnt>1){
					cout << "DIFFERENT" << endl;
				}
				else{
					cout << "CLOSE" << endl;
				}
			}
		}
	}
}