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)
}

Python: while 1:

    s1 = input().split('"')
    if s1 == ['.']:  # 強制終了
        break

    s2 = input().split('"')
    if len(s1) != len(s2):  # 長さが違う場合
        print("DIFFERENT")
        continue

    cnt = 0
    for i in range(len(s1)):
        if s1[i] != s2[i]:
            cnt += 1
            if i%2==0:
                cnt += 2
        else:
            i+=1

    if cnt == 0:
        print("IDENTICAL")  # 完全一致
    elif cnt == 1:
        print("CLOSE")  # 一つ違い
    else:
        print("DIFFERENT")  # それ以外

Python: while 1:
	s1=input().split('"')
	if s1[0]==".":
		break
	s2=input().split('"')
	
	cnt1=0
	cnt2=0
	flag=0
	
	if len(s1)!=len(s2):
		print("DIFFERENT")
	else:
		i=0
		while i<len(s1):
			if s1[i]==s2[i]:
				cnt1+=1
			elif i%2==0:
				print("DIFFERENT")
				flag=1
				break
			else:
				cnt2+=1
				if cnt2>1:
					print("DIFFERENT")
					break
			i+=1
				
		if flag==1:
			break
		elif cnt2==1:
			print("CLOSE")
		elif cnt1==len(s1):
			print("IDENTICAL")

Python: while(True):
    s1 = input()
    if (s1 == '.'):
        break
    s2 = input()

    ans = None
    if s1 == s2:
        ans = 'IDENTICAL'

    if ans is None:
        s1 = s1.split('"')
        s2 = s2.split('"')
        if len(s1) == len(s2):
            miss = 0
            for p1, p2 in zip(s1[0::2], s2[0::2]):
                if p1 != p2:
                    miss = 2
            for p1, p2 in zip(s1[1::2], s2[1::2]):
                if p1 != p2:
                    miss += 1
            if miss <= 1:
                ans = 'CLOSE'

    if ans is None:
        ans = 'DIFFERENT'

    print(ans)

Python: while 1:
    s1 = input().split('"')
    l1 = len(s1)
    if s1[0] == ".": break
    s2 = input().split('"')
    l2 = len(s2)
    if l1 != l2:
        print("DIFFERENT")
        break
    i = 0
    j = 0
    k = 0
    flag_1 = 0
    flag_2 = 0
    cnt = 0
    x1 = []
    x2 = []
    while 1:
        if i > l1-2:
            if cnt == 1:
                print("CLOSE")
                break
            else:
                print("IDENTICAL")
                break
        if s1[i] != s2[i]:
            print("DIFFERENT")
            break
        if s1[i+1] != s2[i+1]:
            if cnt == 1:
                print("DIFFERENT")
                break
            else: cnt = 1
        i += 2

Python: s1 = list(str(input()))
while s1!= '.':
    s2 = list(str(input()))
    if s1 == s2:
        print("IDENTICAL")
    else:
        tmp1 = 0
        tmp2 = 0
        key = 0
        while tmp1 != len(s1)-1 or tmp2 != len(s2)-1:
            str1 = []
            str2 = []
            str3 = []
            str4 = []
            n1 = 0
            n2 = 0
            for i in range(tmp1, len(s1)):
                if s1[i] != '"':
                    str1.append(s1[i])
                    tmp1 = i
                if s1[i] == '"':
                    n1 = 1
                    j = i
                    for k in range(j+1, len(s1)):
                        if s1[k] == '"':
                            tmp1 = k+1
                            break
                        str3.append(s1[k])
                if n1 == 1:
                    break

            for i in range(tmp2, len(s2)):
                if s2[i] != '"':
                    str2.append(s2[i])
                    tmp2 = i
                if s2[i] == '"':
                    n2 = 1
                    j = i
                    for k in range(j+1, len(s2)):
                        if s2[k] == '"':
                            tmp2 = k+1
                            break
                        str4.append(s2[k])
                if n2 == 1:
                    break
            print(str1, str2, str3, str4)
            if str3 == str4:
                pass
            elif str3 != str4:
                key += 1
            if str1 != str2 or key >= 2:
                print("DIFFERENT")
                break

        if key == 1 and str1 == str2:
            print("CLOSE")
    s1 = list(str(input()))

Python: import re

def solve(s, t):
	if s == t:
		return "IDENTICAL"
	s = s.split("\"")
	t = t.split("\"")
	if len(s) == len(t):
		a = sum(s[i] != t[i] for i in range(0, len(s), 2))
		b = sum(s[i] != t[i] for i in range(1, len(s), 2))
		if a == 0 and b == 1:
			return "CLOSE"
	return "DIFFERENT"

while True:
	s = input()
	if s == ".":
		break
	t = input()
	print(solve(s, t))

Python: A1=[]
A2=[]
ans=[]
for i in range(100):
    cnt=0
    S1=input("プログラム1:")
    if S1=='.':
        break
    S2=input("プログラム2:")
    A1=S1.split('"')
    A2=S2.split('"')
    if len(A1)==len(A2):
        for j in range(len(A1)):
            if j%2!=0:
                if A1[j]!=A2[j]:
                    cnt=cnt+1
                else:
                    if A1[j]!=A2[j]:
                        cnt=cnt+10000
    else:
        cnt=cnt+10000
    if cnt>1:
        ans.append("DIFERENT")
    elif cnt==1:
        ans.append("CLOSE")
    else:
        ans.append("IDENTICAL")
for i in range(len(ans)):
    print(ans[i])

Python: def is_same(s1, s2):
  sp1 = s1.split("\"")
  sp2 = s2.split("\"")
  if len(sp1) != len(sp2):
    return 2
  
  count = 0
  for i in range(len(sp1)):
    if i % 2 == 0:
      if sp1[i] != sp2[i]:
        return 2
    else:
      if sp1[i] != sp2[i]:
        count += 1
        if count >= 2:
          return 2
  return count

while True:
  s1 = input()
  if s1 == ".":
    break
  s2 = input()
  result = is_same(s1, s2)
  if result == 0:
    print("IDENTICAL")
  elif result == 1:
    print("CLOSE")
  else:
    print("DIFFERENT")