Go: package main

import (
	"bufio"
	"os"
	"strings"
	"fmt"
	"reflect"
)

var scanner = bufio.NewScanner(os.Stdin)

func nextString() string {
	scanner.Scan()
	return scanner.Text()
}

func cipher(text string, direction int, int_shift int) string {
	shift, offset := rune(int_shift), rune(26)
	runes := []rune(text)
	for index, char := range runes {
		switch direction {
		case 1:
			if char >= 'a' && char <= 'z'-shift || char >= 'A' && char <= 'Z'-shift {
				char = char + shift
			} else if char > 'z'-shift && char <= 'z' || char > 'Z'-shift && char <= 'Z' {
				char = char + shift - offset
			}
		case -1:
			if char >= 'a'+shift && char <= 'z' || char >= 'A'+shift && char <= 'Z' {
				char = char - shift
			} else if char >= 'a' && char < 'a'+shift || char >= 'A' && char < 'A'+shift {
				char = char - shift + offset
			}
		}
		runes[index] = char
	}
	return string(runes)
}

func main() {
	for {
		infos := strings.Split(nextString(), " ")
		plain := make([]string, len(infos))
		if reflect.DeepEqual(infos, []string{}) {
			break
		}
		fmt.Println(infos)
		Decryption:
			for i := 0; i < 26; i++ {
				for j := range infos {
					plain[j] = cipher(infos[j], 1, i)
				}
				for j := range plain {
					if plain[j] == "this" || plain[j] == "that" || plain[j] == "the" {
						break Decryption
					}
				}
			}
			fmt.Println(strings.Join(plain, " "))
	}
}

C++: #include <iostream>
#include <iomanip>
#include <vector>
#include <string>
#include <stack>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <algorithm>
#include <sstream>
#include <cstdlib>
#include <cstring>
#include <functional>
#include <numeric>
#include <cmath>
#include <climits>
#include <limits>
#include <cfloat>
#include <fstream>
using namespace std;

int main()
{
	const string key[] = { "the", "this", "that" };
//	cut here before submit 
//	freopen("testcase.cc", "r", stdin);
	string str = "";
	
	while (getline (cin, str )){
		int len = str.length();
		int i,j;

		for (j = 1; j < 26; ++j){
			string curr = str;
			for (i = 0; i < len; ++i){
				if ( isalpha(curr[i]) ){
					if (isupper(curr[i])){
						curr[i] = (curr[i] - 'A' + j) % 26 + 'A';
					}else if (islower(curr[i])){
						curr[i] = (curr[i] - 'a' + j) % 26 + 'a';
					} // end if
				} // end if
			} // end for
			for (i = 0; i < 3; ++i){
				if ( curr.find(key[i]) != string::npos ){
					cout << curr << endl;
					goto next;
				} // end if
			} // end for
		} // end for
next:
	;
	} // end while
		
	return 0;
}

C++: #define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <stdio.h>
#include <string>
#include <vector>
using namespace std;

int main() {
	char s[81] = {};
	while (fgets(s,sizeof(s),stdin)) {
		int start = 0, ofs=0,ofs2,chk=1;
		char buf;
		for (int i = 0; s[i] != '\n'; i++) {
			cout << "start=" << start << endl;
			if (s[i] == ' ' || s[i] == '.') {
				if (i - start == 3) {
					cout << "a\n";
					chk = 1;
					ofs2 = (int)'t' - (int)s[start];
					for (int j = 1; j < 3; j++) {
						buf = s[start + j] + ofs2;
						if (buf > 'z')
							buf -= 26;
						if (buf < 'a')
							buf += 26;
						if (j == 1 && buf != 'h') {
							chk = 0;
							break;
						}
						if (j == 2 && buf != 'e')
							chk = 0;
					}
					if (chk == 1) {
						ofs = ofs2;
						cout << ofs << endl;
						break;
					}
				}
				if (i - start == 4) {
					cout << "b\n";
					chk = 0;
					ofs2 = (int)'t' - (int)s[start];
					for (int j = 1; j < 3; j++) {
						buf = s[start + j] + ofs2;
						if (buf < 'z')
							buf -= 26;
						if (buf > 'a')
							buf += 26;
						if (j == 1 && buf != 'h') {
							chk = 0;
							break;
						}
						if (j == 2 && buf == 'a')
							chk = 2;
						if (j == 2 && buf == 'i')
							chk = 3;
						if (j == 2 && buf != 'i'&&buf != 'i') {
							chk = 0;
							break;
						}
						if (j == 3 && chk == 2) {
							if (buf == 't')
								chk = 1;
							else {
								chk = 0;
								break;
							}
						}
						if (j == 3 && chk == 3) {
							if (buf == 's')
								chk = 1;
							else {
								chk = 0;
								break;
							}
						}
					}
					if (chk == 1) {
						ofs = ofs2;
						cout << ofs << endl;
						break;
					}
				}
				start = i + 1;
			}
		}
		for (int i = 0; s[i] != '\n'; i++) {
			if (s[i] != ' '&& s[i]!='.') {
				s[i] += ofs;
				if (s[i] > 'z')
					s[i] -= 26;
				if (s[i] < 'a')
					s[i] += 26;
			}
		}
		cout << s;
	}
	return 0;
}

C++: #include <iostream>
#include <string>
using namespace std;
 
int main(void) {

  string str;
   
  while(getline(cin, str)) {
    while(1) {
      for(int i=0; i<str.length(); i++) {
          if(str[i] != ' ' && str[i] != '.') {
              if(str[i] != 'z'){
                        str[i] += 1;
                    }else{
                        str[i] = 'a';
                    }
          }
      }
      

          if(str.find("the")!=string::npos||str.find("this")!=string::npos||str.find("that")!=string::npos) {
          cout << str << endl;
          break;
      
    }
    }
  }
  return 0;
}

C++: #include <iostream>
#include <algorithm>
#include<string>
#include<vector>
int main() {
	std::string s,a;
	std::getline (std::cin , s);
	int p = s[0] - 't';
	for (int i = 0; i < s.size(); ++i) {
		if (s[i] != ' ' &&s[i]!= '.') {
			if (s[i] - p < 'a') {
				a += 'z' - ('a' - (s[i] - p)-1);
			}
			else a += s[i] - p;
		}
		else a += s[i];
	}
	std::cout << a<< std::endl;
	return 0;
}

C++: #include <iostream>
using namespace std;

int cmp(string s){
	if(s.find("that",0)!=string::npos) return 1;
	if(s.find("the",0)!=string::npos) return 1;
	if(s.find("this",0)!=string::npos) return 1;
	return 0;
}

int main() {
	string s;
	getline(cin,s);
	for(int h=0;h<26;h++){
		for(unsigned int i=0;i<s.length();i++){
				if(s[i]==0x2e||s[i]==0x20||s[i]==0x0a) continue;
				s[i]+=1;
				if((int)s[i]>0x7a) s[i]=0x61;
		}if(cmp(s)==1) break;
	} cout<<s<<endl;
	return 0;
}

C++: #include <iostream>
#include <string>

using namespace std;

int main()
{
  string stro, str;
  while(getline(cin, stro)){
    for(int i = 0; i < 26; i++){
      str = stro;
      for(int j = 0; j < stro.length(); j++){
	if(str[j] >= 'a' && str[j] <= 'z')
	  if(str[j] + i > 'z')
	    str[j] += i - 26;
	  else
	    str[j] += i;
      }
      unsigned f_the = str.find("the", 0);
      unsigned f_this = str.find("this", 0);
      unsigned f_that = str.find("that", 0);
      if((f_the != string::npos && f_the == 0 && (str[f_the + 3] == ' ' || str[f_the + 3] == '.' || str[f_the + 3] == '\0')) || (f_this != string::npos && f_this == 0 && (str[f_this + 4] == ' ' || str[f_this + 4] == '.' || str[f_this + 4] == '\0')) || (f_that != string::npos && f_that == 0 && (str[f_that + 4] == ' ' || str[f_that + 4] == '.' || str[f_that + 4] == '\0')))
	cout << str << endl;
      else if((f_the != string::npos && (str[f_the - 1] == ' ' || str[f_the - 1] == '.' || str[f_the - 1] == '\n') && (str[f_the + 3] == ' ' || str[f_the + 3] == '.' || str[f_the + 3] == '\0')) || (f_this != string::npos && (str[f_this - 1] == ' ' || str[f_this - 1] == '.' || str[f_this - 1] == '\n') && (str[f_this + 4] == ' ' || str[f_this + 4] == '.' || str[f_this + 4] == '\0')) || (f_that != string::npos && (str[f_that - 1] == ' ' || str[f_that - 1] == '.' || str[f_that - 1] == '\n') && (str[f_that + 4] == ' ' || str[f_that + 4] == '.' || str[f_that + 4] == '\0')))
	cout << str << endl;	 
    }
  }
}

C++: #include <iostream>
#include <string>
using namespace std;
int caesar(char s[]);
bool search(string s);

int main(){
	string str;
	unsigned int i;
	while(getline(cin,str)){
		int j=0;
		while(!search(str)){
			for(i=0;i<str.length();i++){
				if(str[i]!=' '&&str[i]!='.') str[i]++;
				if(str[i]>122) str[i]=97;
			}
			j++;
			if(j>25) break;
		}
		cout << str << endl;
	}
	return 0;
}

bool search(string s){
	if(s.find("this")!=string::npos) return true;
	if(s.find("that")!=string::npos) return true;
	if(s.find("the")!=string::npos) return true;
	return false;
}