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 <vector>

using namespace std;

int main()
{
  while(1){
    string row1,row2;
    string period(".");
    string cover("\"");

    cin>>row1;
    if(row1 == period){
      break;
    }
    cin>>row2;

    if(row1 == row2){
      cout<<"IDENTICAL"<<endl;
    }
    else{
      int size1 = row1.size();
      vector<string> Row1;
      int j = 0;
      string temp2;

      for(int i = 0;i < size1;++i){ 
        string temp1;
        temp1 = row1[i];
        if(temp1 == cover){
          string temp4;
          Row1.push_back(temp2);
          temp2 = temp4;
        }
        else if(i == size1 - 1){
          temp2 += temp1;
          Row1.push_back(temp2);
        }
        else{
          temp2 += temp1;
        }
      }

      int size2 = row2.size();
      vector<string> Row2;
      string temp3;

      for(int i = 0;i < size2;++i){ 
        string temp1;
        temp1 = row2[i];
        if(temp1 == cover){
          string temp4;
          Row2.push_back(temp3);
          temp3 = temp4;
        }
        else if(i == size2 - 1){
          temp3 += temp1;
          Row2.push_back(temp3);
        }
        else{
          temp3 += temp1;
        }
      }




      int Size1 = Row1.size();
      int Size2 = Row2.size();
      int count = 0;

      if(Size1 != Size2){
        cout<<"DIFFERENT"<<endl;
      }
      else{
        for(int i = 1;i <= Size1;++i){
          string check1,check2;
          check1 = Row1[i];
          check2 = Row2[i];

          if(i % 2 == 1){
            if(check1 != check2){
              cout<<"DIFFERENT"<<endl;
              break;
            }
          }
          else{
            if(check1 != check2){
              ++count;
            }
          }

          if(count >= 2){
            cout<<"DIFFERENT"<<endl;
            break;
          }
        }
      }

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

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

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,str1;
	std::string s2,str2;
	std::vector<std::string> ans;

	while(1){
		std::cin>>str1;

		
		i=0;
		while(str1[i]!=NULL){
			s1.push_back(str1[i]);
			i++;
		}
//		std::cout<<s1<<"\n";
		if(s1=="."){
//			std::cout<<s1<<"\n";
			break;
		}
		std::cin>>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){
					if(s1[j]!='"'){
						while(s1[j]!='"'){
							j++;
						}
						scou1++;
						flag2=2;
						flag3=1;
					}else{
						flag2=1;
						break;
					}
				}else if(scou2%2==1){
					if(s2[m]!='"'){
						while(s2[m]!='"'){
							m++;
						}
						scou2++;
						flag2=2;
						flag3=1;
					}else{
						flag2=1;
						break;
					}
				}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;
}