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


int main()
{
	string str;
	int len;
	int i,j;
	while(1) {
		getline(cin,str);
		if(cin.eof())
			break;

		len = str.length();
		for(i = 0; i < 26; i++ ) {
			for ( j = 0; j < len; j++ ) {
				if ( 'a' <= str[j] && str[j] <= 'z') {
					str[j]++;
					if ( str[j] > 'z')
						str[j] = '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<string>
using namespace std;

int main(){
  string word;
  string com[3]={"the","this","that"};
  int cou=0;

  while(1){
    //bool flag = false;
    getline(cin,word);
    if(cin.eof()){
      break;
    }
    while(1){
      bool flag = false;
      for(int i=0;i<word.size();i++){
	if(word[i] == 'z'){
	  word[i] = 'a';
	}
	else if(word[i] >= 'a' && word[i] <= 'z'){
	  word[i]++;
	}
      }
      for(int i=0;i<3;i++){
	int index = word.find(com[i],0);
	if(index != string::npos){
	  cout << word << endl;
	  flag = true;
	  break;
	}
      }
      if(flag == true) break;
    }
  }
}

C++: #include <bits/stdc++.h>

using namespace std;

int main() {
	string str;
	while (getline(cin, str)) {
		int cnt = 0;
		for (int i = 0; i < 26; ++i) {
			for (int j = 0; j < (int)str.size(); ++j) {
				if (str[j] >= 'a' && str[j] <= 'z') {
					str[j] = (str[j] - 'a' + 1) % 26 + 'a';
				}
			}
			cnt++;
			if (str.find("the") != string::npos || str.find("this") != string::npos || str.find("that") != string::npos) break;
		}
		for (int i = 0; i < 26; ++i) {
			for (int j = 0; j < (int)str.size(); ++j) {
				if (str[j] >= 'a' && str[j] <= 'z') {
					str[j] = (str[j] - 'a' + cnt) % 26 + 'a';
				}
			}
		}
		cout << str << endl;
	}
}

C++: #include<bits/stdc++.h>
using namespace std;
int main()
{
    string str;
    while(getline(cin,str)){
            while(1){
                if(str.find("the")!=-1||str.find("that")!=-1||str.find("this")!=-1)break;
                for(int i=0;i<str.size();i++){
                    if(str[i]=='.'||str[i]==' '){}
                    else str[i]--;
                }
            }
            cout<<str<<endl;
    }

}

C++: #include <bits/stdc++.h>

using namespace std;

int main (){
    //freopen("input.txt" , "r", stdin);
    string str1;
    while(getline (cin, str1)){
            
    int cnt =0;

    for(int i=1; i<27; i++){

        cnt++;

        for(int j=0; j<str1.size(); j++){
            if(str1[j]>= 'a' && str1[j]<= 'z'){
                int ascii = (int)  97+ (((str1[j] % 97) + 1) %26);
                str1[j] = ascii;
            }
            else str1[j] = str1[j];
        }

        //cout<<str1<<endl;

        int position =0, flag =0;

        if((position = (str1.find("this"))) != -1 ){
            flag = 1;
            break;
        }

        else if((position = (str1.find("the"))) != -1 ){
            flag = 1;
            break;
        }

        else if((position = (str1.find("that"))) != -1 ){
            flag = 1;
            break;
        }
    }

    //cout<<"The key: "<<cnt<<endl;
    cout<<str1<<endl;
    str1.clear();

    }


    return 0;
}

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

int main() {
  string str,s;
  int key,word;
  vector<string> seq;
  char decode[4],ans;
  while(getline(cin,str)) {
    seq.clear();
    stringstream ss;
    ss << str;
    while(ss >> s) {
      seq.push_back(s);
    }
    ss.str("");
    ss.clear(stringstream::goodbit);

    word = seq.size();
    key = 100;

    for(int i=0;i<word;i++) {

	decode[0] = *seq[i].substr(0,1).c_str();
	decode[1] = *seq[i].substr(1,1).c_str();
	decode[2] = *seq[i].substr(2,1).c_str();
	decode[3] = *seq[i].substr(3,1).c_str();

	for(int j=1;j<27;j++) {
	  for(int k=0;k<4;k++) {
	    decode[k] -= 97; //a-z 0-25
	    decode[k]++;//1-26
	    decode[k] %= 26;//0-25
	    decode[k] += 97;//97-122
	  }
	  if( (decode[0] == 't' && decode[1] == 'h' && decode[2] == 'e') && (seq[i].size() == 3)) {
	    key = j;
	    break;
	  }
	  if( (decode[0] == 't' && decode[1] == 'h' && decode[2] == 'i' && decode[3] == 's') && (seq[i].size() == 4) ) {
	    key = j;
	    break;
	  }
	  if( (decode[0] == 't' && decode[1] == 'h' && decode[2] == 'a' && decode[3] == 't') && (seq[i].size() == 4) ){
	    key = j;
	    break;
	  }
	}
      
      if(key!=100) break;
    }

    for(int i=0;i<word;i++) {
      for(unsigned int j=0;j<seq[i].size();j++) {
	ans = *seq[i].substr(j,1).c_str();
	if(ans <= 'z' && 'a' <= ans){
	  ans -= 97;
	  ans += key;
	  ans %= 26;
	  ans += 97;
	}
	cout << ans;
      }
      if(i==word-1) {
	break;
      }
      cout << " ";
      
    }
    cout << endl;
  }
}

C++: #include <bits/stdc++.h>

using namespace std;

int main() {
	string str;
	while (getline(cin, str)) {
		for (int i = 0; i < 26; ++i) {
			for (int j = 0; j < (int)str.size(); ++j) {
				if (str[j] >= 'a' && str[j] <= 'z') {
					str[j] = (str[j] - 'a' + 1) % 26 + 'a';
				}
			}
			if (str.find("the") != string::npos || str.find("this") != string::npos || str.find("that") != string::npos) break;
		}
		cout << str << endl;
	}
}

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

int main()
{
    string s;
    while(getline(cin,s))
	{
        for(int i=0;i<26;++i)
		{
            for(int j=0;j<s.size();++j) 
				if('a'<=s[j]&&s[j]<='z')
					
						s[j]=((s[j]-'a'+1)%26+'a');
				 }
        cout<<s<<endl;
    }
    return 0;
}