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;

string str;

bool caesar()
{
	bool flag = false;

	for (int i=0; i<(int)str.size() - 2; i++)
	{
		if(str[i] == 't' && str[i+1] == 'h') {
			if(str[i+2] == 'e' && (str[i+3] == ' ' || str[i+3] == '\0' || str[i+3] == '.')) {
				flag = true;
				break;
			}
			if(str[i+2] == 'i' && str[i+3] == 's' && (str[i+4] == ' ' || str[i+4] == '\0' || str[i+4] == '.')) {
				flag = true;
				break;
			}
			if(str[i+2] == 's' && str[i+3] == 't' && (str[i+4] == ' ' || str[i+4] == '\0' || str[i+4] == '.')) {
				flag = true;
				break;
			}
		}
	}

	return flag;
}


int main()
{
	while(getline(cin, str))
	{
		for (int i=0; i<26; i++)	//0〜25文字ずれるまで繰り返す
		{
			if(caesar()) {
				cout << str << endl;
			}

			//cout << str << endl;	//Debug

			for (int j=0; str[j] != '\0'; j++) {
				if(str[j] != ' ' && str[j] != '.') {
					if(str[j] == 'z') {
						str[j] = 'a';
					}
					else {
						str[j]++;
					}
				}
			}
		}
	}

	return 0;
}

C++: #include <iostream>
#include <string>
using namespace std;
int main()
{
	string str;
	while(getline(cin,str))
	{
		bool flag=false;
		for(int k=0;k<26;k++)
		{
			int i=0;
			for(i=0;i<str.size();i++)
			{
				if(str[i]-'a'<0 || str[i]-'z'>0) continue;
				else { str[i]++; if(str[i]-'z'>0) str[i]-=26; }
			};
			string ptr,qtr;
			for(i=0;i<str.size();i++)
			{
				if(i+4<str.size()) ptr=str.substr(i,4);
				if(i+3<str.size()) qtr=str.substr(i,3);
				if(ptr=="this" || ptr=="that" || qtr=="the") {flag=true; break;}
			};
			if(flag==true) break;
		};
		cout << str << endl ;
	}
}

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

int main(){

  string s;

  while(getline(cin,s)){
    while(s.find("the")==string::npos && s.find("this")==string::npos && s.find("that")==string::npos){
      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';
        }
      }
    }
    cout << s << endl;
  }


  return 0;
}

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

bool is_valid(const std::string& str) {
	if (str.find("the ") != std::string::npos
		|| str.find("this ") != std::string::npos
		|| str.find("that ") != std::string::npos
		|| str.find(" the ") != std::string::npos
		|| str.find(" this ") != std::string::npos
		|| str.find(" that ") != std::string::npos
		|| str.find(" the") != std::string::npos
		|| str.find(" this") != std::string::npos
		|| str.find(" that") != std::string::npos) {
		return true;		
	}
	return false;
}

int main() {
	std::string str;
	std::getline(std::cin, str);
	
	std::string ans;
	const int limit = 'z' - 'a' + 1;
	for (int i = 0; i < limit; ++i) {
		for (auto c : str) {
			int elem = c + i;
			if (c >= 'a' && c <= 'z') {
				if (elem > 'z') {
					elem = 'a' + elem - ('z' + 1);
				}
				ans.push_back(elem);
			} else {
				ans.push_back(c);
			}
		}
		if (is_valid(ans)) {
			break;
		}
		ans.clear();
	}
	
	std::cout << ans << std::endl;
}

C++: #include <string>
#include <vector>
#include <algorithm>
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <queue>
#include <map>
#define INF 100000000
#define rep(i,a) for(int i=0;i<(a);i++)

using namespace std;
typedef long long ll;

char p(char ch){
    char ret=ch+1;
    if(ret==('{'))ret='a';
    return ret;
}


int main(){
    string s;
    getline(cin,s);


    rep(i,30){
        rep(i,s.size()){
            if(s[i]!=' ' && s[i]!='.'){
                s[i]=p(s[i]);
            }
        }

        if( s.find("the",0)!=-1 || s.find("this",0)!=-1 || s.find("that",0)!=-1 ){
            cout<<s<<endl;
            break;
        }
    }
    
    return 0;
    
}

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

using namespace std;

string line;
int str_len;

bool is_finish() {
  for(int i=0; i<str_len-3; i++) {
    if(line[i] == 't') {
      if(line[i+1] == 'h') {
        if(line[i+2] == 'e') { return true; }
        else if(line[i+3] == 'i' && line[i+4] == 's') { return true; }
        else if(line[i+3] == 'a' && line[i+4] == 't') { return true; }
      }
    }
  }
  return false;
};


int main() {
  getline(cin, line);
  str_len = line.length();
  
  for(int j=0; j<26; j++) {
    if(is_finish()) { 
      cout << line << endl;
      break; 
    }

    for(int j=0; j<str_len; j++) {
      if('a' <= line[j] && line[j] < 'z') {
        line[j] += 1;
      }
      else if(line[j] == 'z') {
        line[j] = 'a';
      }
    }
  }
  return 0;
}

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

  //  string x;
  char x[100];
  gets(x);
  //  cin >> x;
  bool is = true;
  if(strlen(x) >= 3){
    for(int i = 0; i < 26 ; i++){
      //the 
      for(int j = 0; j <= strlen(x)-3; j++){
	if(is && x[j] =='t' && x[j+1] == 'h' && x[j+2] == 'e'){
	  is = false;
	  break;
	}
      }
      // this or that
      if(strlen(x) >= 4){
	for(int j = 0; j <= strlen(x)-4; j++){
	  if(is && x[j] =='t' && x[j+1] == 'h' && x[j+2] == 'a' && x[j+3] =='t' ){
	    is = false;
	    break;
	  }
	  if(is && x[j] =='t' && x[j+1] == 'h' && x[j+2] == 'i' && x[j+3] =='s' ){
	    is = false;
	    break;
	  }
	}
      }
      // increment
      if(is == false) break; 
      for(int j = 0; j < strlen(x) ; j++){
	if(x[j] == ' ') x[j] = ' ';
	else if(x[j] == 'z') x[j] = 'a';
	else if(x[j] >= 'a' && x[j] < 'z') x[j]++;
      }
    }
    
    if(is == false)	
      cout << x << endl;
  }
  return 0;
}

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

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

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

void next(string& str)
{
	for(int i=0; i<str.length(); i++)
	{
		if('a'<=str[i] && str[i]<='z')
		{
			str[i] = ((str[i]-'a'+25)%26)+'a';
		}
	}
}

int main()
{
	string str;
	while(getline(cin,str))
	{
		for(int i=0; i<26; ++i,next(str))
		{
			if(-1!=str.find("the") || -1!=str.find("this") || -1!=str.find("that"))
			{
				cout << str << endl;
				break;
			}
		}
	}

	return 0;
}