Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

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

func incrementByte(b byte) byte {
	if b >= 97 && b < 122 {
		return b + 1
	} else if b == 122 {
		return 97
	}
	return b
}

func main() {
	scanner.Split(bufio.ScanLines)

	for {
		line := nextString()
		if len(line) == 0 {
			break
		}
		for i := 0; i <= 26; i++ {
			decoded := []byte{}
			for j := 0; j < len(line); j++ {
				decoded = append(decoded, incrementByte(line[j]))
			}
			line = string(decoded)
			if strings.Contains(line, "the") || strings.Contains(line, "this") || strings.Contains(line, "that") {
				fmt.Println(line)
				break
			}
		}
	}
}

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;
}

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

using namespace std;

int main() {
    string s;
    int len;
    
    while (getline(cin, s)) {
        while (1) {
            len = s.size();
            for (int i = 0; i < len; i++) {
                if ('a' <= s[i] && s[i] <= 'z') {
                    if (s[i] == 'a') {
                        s[i] = 'z';
                    }
                    else {
                        s[i]--;
                    }
                }
            }
            if (s.find("the") >= 0 || s.find("this") >= 0 || s.find("that") >= 0) {
                cout << s << endl;
                break;
            }
        }
    }

    return 0;
}

C++: #include <iostream>
#include <vector>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <functional>
#include <string>
#include <algorithm>
#include <string>
#include <climits>
#include <iomanip>
#include <utility>

#define REP(i, n) for (int (i) = 0; (i) < (int)(n); (i)++)
#define REG(i, a, b) for (int (i) = ((int)(a)); (i) < ((int)(b)); i++)
#define ALL(V) (V).begin(), (V).end()
#define PRINT(STR) cout << (STR) << endl
#define DEBUG(X) cerr << X << " (" << __LINE__ << ", " << __func__ << " )" << endl;

typedef long long ll;
using namespace std;

int main() {
	cin.tie(0); //?????±?????????????????????
	ios::sync_with_stdio(false); //printf??¨??±??????????????????
	string str;
	while (getline(cin, str)) {
		string newstr = str;
		for (int i = -26; i <= 26; i++) {
			for (int j = 0; j < str.size(); j++) {
				if (newstr[j] != ' ' && newstr[j] != '.' && newstr[j] != '\n') {
					newstr[j] = str[j] + i;
				}
			}
			if (newstr.find("the", 0) != string::npos ||
					newstr.find("this", 0) != string::npos ||
					newstr.find("that", 0) != string::npos) {
				cout << newstr << endl;
				break;
			}
		}
	}
	return 0;
}

C++: #include<iostream>
#include<cstdio>
#include<cmath>
#include<vector>
#include<list>
#include<set>
#include<map>
#include<stack>
#include<queue>
#include<string>
#include<utility>
#include<algorithm>
#include<functional>
#include<deque>
#include<string.h>
#include<ctype.h>
#include<time.h>
#include<stdlib.h>
using namespace std;

char c[80], word[80][15];
int p = 0, q = 0;

bool search_th(){
  for (int i = 0; i < p; i++){
    if (word[i][0] == 't' && word[i][1] == 'h'){
      if (word[i][2] == 'e' || (word[i][2] == 'i' && word[i][3] == 's') || (word[i][2] == 'a' && word[i][3] == 't')){
        return true;
      }
    }
  }
  return false;
}

void split_words(){
  for (int i = 0; i < 80; i++){
    for (int j = 0; j < 15; j++){
      word[i][j] = '\0';
    }
  }
  for (int i = 0; i < strlen(c); i++){
    if (c[i] >= 'a' && c[i] <= 'z'){
      word[p][q++] = c[i];
    } else {
      p++;
      word[p++][0] = c[i];
    }
  }
}

int main(){
  while (cin.getline(c, sizeof(c))){
    split_words();
    while (1){
      if (search_th() == true){
        for (int i = 0; i < p; i++){
          cout << word[i];
        }
        puts("");  break;
      } else {
        for (int i = 0; i < p; i++){
          for (int j = 0; j < strlen(word[i]); j++){
            if (word[i][j] >= 'a' && word[i][j] <= 'y') word[i][j]++;
            if (word[i][j] == 'z')                      word[i][j] = 'a';
          }
        }
      }
    }
    for (int i = 0; i < 80; i++){
      c[i] = '\0';
    }
  }
  return 0;
}

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

int main(){
	std::string s;
	while(std::getline(std::cin,s)){
		while(s.find("the")==s.npos&&s.find("that")==s.npos&&s.find("this")==s.npos){
			for(int i=0;i<s.size();++i){
				if(s[i]>='a'&&s[i]<='y')s[i]++;
				else if(s[i]=='z')s[i]='a';
			}
		}
		std::cout<<s<<std::endl;
	}
	return 0;
}

C++: #include<cstring>
#include<cstdio>
#include<iostream>

#define REP(n) for(int i=0;i<n;i++)

using namespace std;


int main(){
	char a[100];

	while(NULL!=fgets( a, 80, stdin)){
		int n=strlen(a);

		while(NULL==strstr(a,"the")&&NULL==strstr(a,"this")&&NULL==strstr(a,"that")){
			REP(n){
				if('a'<=a[i] && a[i]<'z')	a[i]++;
				else if('z'==a[i]) a[i]='a';
			}
		}

	fprintf(stdout, "%s\n",a);
	}

	return 0;
}