Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

func main() {
	for scanner.Scan() {
		var result string
		line := scanner.Text()
		key := make(map[string]string)

		var i int32
		for ; i < 52; i++ {
			makeKey(key, i)
			result = decode(key, line)

			if strings.Contains(result, "the") {
				break
			} else if strings.Contains(result, "this") {
				break
			} else if strings.Contains(result, "that") {
				break
			}
		}

		fmt.Println(result)
	}
}

func makeKey(key map[string]string, shift int32) {
	for i := 'a'; i <= 'z'; i++ {
		cipher := (i + shift)
		if cipher > 'z' {
			cipher = cipher%'z' + 'a' - 1
		} else if cipher < 'a' {
			cipher = cipher + ('z' - 'a') + 1
		}
		key[string(i)] = string(cipher)
	}
}

func decode(key map[string]string, cipher string) string {
	var result string
	for _, v := range cipher {
		if key[string(v)] != "" {
			result += key[string(v)]
		} else {
			result += string(v)
		}
	}
	return result
}

C++: // includes
#include <cstdio>
#include <cstdint>
#include <iostream>
#include <iomanip>
#include <string>
#include <queue>
#include <stack>
#include <vector>
#include <set>
#include <map>
#include <unordered_map>
#include <algorithm>
#include <utility>
#include <functional>
#include <cmath>
#include <climits>
#include <bitset>

// macros
#define ll long long int
#define pb push_back
#define mk make_pair
#define pq priority_queue
#define FOR(i, a, b) for(int i=(a); i<(b);++i)
#define rep(i, n) FOR(i, 0, n)

using namespace std;

//  types
typedef pair<int, int> P;
typedef pair<ll, int> Pl;
typedef pair<ll, ll> Pll;
 
// constants
const int inf = 1e9;
const ll linf = 1LL << 50;
const double EPS = 1e-10;

// solve

int main(int argc, char const* argv[])
{
  string s;
  while(getline(cin, s)){
    FOR(i, 1, 27){
      string t = s;
      string res = "";
      rep(j, t.size()){
        if(!('a' <= s[j] && s[j] <= 'z')){
          res += t[j];
        }else{
          res += char(((int(t[j] - 'a') + i) % 26) + 'a');
        }
      }
      string tmp = "";
      bool flag = false;
      rep(j, res.size()){
        if(res[j] != ' ' && res[j] != '.')tmp += res[j];
        else{
          if(tmp == "the" || tmp == "this" || tmp == "that"){
            flag = true;
            break;
          }
          tmp = "";
        }
      }
      if(tmp == "the" || tmp == "this" || tmp == "that"){
        flag = true;
      }
      if(flag){
        cout << res << endl;
        break;
      }
    }
  }
	return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <sstream>

using namespace std;

bool is_comprehensible(const string& str){
	istringstream iss(str);
	string word;
	while(iss >> word){
		if(word == "the" || word == "this" || word == "that"){
			return true;
		}
	}
	return false;
}

string shift_string(const string& str, char n){
	string result;
	for(auto& v: str){
		if('a' <= v && v <= 'z'){
			result += (v - 'a' + n) % 26 + 'a';
		}
		else{
			result += v;
		}
	}
	return result;
}

int main(){
	string str;
	getline(cin, str);
	
	for(int i = 0; i < 26; ++i){
		auto shifted = shift_string(str, i);
		if(is_comprehensible(shifted)){
			cout << shifted << endl;
			break;
		}
	}
	return 0;
}

C++: #include <iostream>
#include <string>
#include <string.h>
using namespace std;
int main(){
	string alpha = "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz";
	string str;
	getline( cin, str );
	for( int a = 0; a < 26; a++ ){
		for( int i = 0; i < str.length(); i++ ){
			//if( str[i] == ' ' ) cout << ' ';
			for( int j = 0; j < alpha.length(); j++ ){
				if( str[i] == alpha[j] ){
					str[i] = alpha[j + 1];
					break;
				}
			}
		}
		/*char word = strtok( str.c_str(), " " );
		if( word == "the" || word == "that" || word == "this" ) break;
		while( word == NULL ){
			word = strtok( NULL, ' ' );
			if( word == "the" || word == "that" || word == "this" ) goto end;
		}*/
		if( str.find("the") != string::npos || str.find("this") != string::npos || str.find("that") != string::npos ){
			break;
		}
	}
	cout << str << endl;
}

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



char slide(char ch, int dif) {
  if( ! isalpha(ch) ) return ch;

  int n = ch - 'a';
  n = (n + dif ) % 26;
  return 'a' + n;
}

int main() {
  for(string line; getline(cin, line); ){
  
  for(int dif = 0; dif < 26; dif++) {
    string str = line;
    
    for(int i = 0; i < (int)str.size(); i++) 
      str[i] = slide( str[i], dif);

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

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

int main() {
  char buf[82];
  char *p;
  int l;
  string str;

  cin.getline(buf, 82);
  l = strlen(buf);

  for (int i=0; i<26; i++) {
    for (int j=0; j<l; j++) {
      if (buf[j]>='a' && buf[j]<='z') {
        buf[j] = (buf[j]-'a'+1)%26 + 'a';
      }
    }
    str.assign(buf);
    if (str.find("the")!=string::npos ||
        str.find("this")!=string::npos ||
        str.find("that")!=string::npos) {
      break;
    }
  }

  cout << str << endl;
  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;

string func(string s){
	for(int i=0;i<s.size();i++){
		if('a'<=s[i] && s[i]<='y')s[i]++;
		else if(s[i]=='z')s[i]='a';
	}
	return s;
}

int main(){
	
	string s;
	while(getline(cin,s)){
		while(true){
			if(s.find("the")!=string::npos)break;
			if(s.find("this")!=string::npos)break;
			if(s.find("that")!=string::npos)break;
			s=func(s);
		}
		cout<<s<<endl;
	}
	
	return 0;
}

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

bool is_contain_keywords(string str,vector<string>& keywords) {
  int cnt = 0;
  vector<string>::iterator key_itr = keywords.begin();
  while(key_itr != keywords.end()) {
    if(str.find(*key_itr) != string::npos) {
      return true;
    }
    key_itr++;
  }
  return false;
}

string decode(string cipher) {
  vector<string> keywords;
  keywords.push_back("the");
  keywords.push_back("this");
  keywords.push_back("that");

  int remind_shift = -1;
  int max_cnt = 0;
  int str_len = cipher.length();
  for(int shift = 0;shift < 'z' - 'a' + 1;shift++) {
    string str = cipher;
    for(int i=0;i<str_len;i++) {
      if('a' <= cipher[i] && cipher[i] <= 'z') {
        str[i] = (cipher[i] - 'a' + shift) % ('z' - 'a' + 1) + 'a';
      }
    }
    if(is_contain_keywords(str,keywords)) return str;
  }
  return "";
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);

  string cipher;
  while(getline(cin,cipher)) {
    cout << decode(cipher) << endl;
  }
}

C++: #define _USE_MATH_DEFINES
#include <iostream>
#include <sstream>
#include <cmath>
#include <algorithm>
#include <queue>
#include <stack>

using namespace std;

int main()
{
	string str;
	while(getline(cin,str)){
		for(int rot = 0;rot< 'z' - 'a' + 1;rot++){
			string tmp = str;
			for(int i=0; i<str.size() - 1; i++){
				if(tmp[i] == ' ') continue;
				tmp[i] = (rot + tmp[i]-'a') % ('z' - 'a' + 1) + 'a';
			}
			//cout << tmp << endl;
			if(tmp.find("the") != string::npos
				|| tmp.find("this") != string::npos
				|| tmp.find("that") != string::npos)
			{
				cout << tmp << endl;
			}
		}
	}
	return 0;
}