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

	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;
	while(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;

void forward(string& data)
{
	for(auto& c : data)
	{
		if(c < 'a' || 'z' < c)
			continue;

		c++;
		if('z' < c)
			c -= 26;
	}
}

bool test(const string& data)
{
	if(data.find("the") != string::npos)
		return true;
	if(data.find("this") != string::npos)
		return true;
	if(data.find("that") != string::npos)
		return true;

	return false;
}

int main()
{
	string line;
	while(getline(cin, line))
	{
		for(int i = 0; i < 26; i++)
		{
			if(test(line))
				break;
			forward(line);
		}

		cout << line << endl;
	}

	return 0;
}

C++: #include <cstdio>
#include <cstdlib>
#include <iostream>
#include <string>
#include <cmath>
#include <algorithm>
#include <vector>
#include <queue>
#include <stack>
#include <map>

using namespace std;
typedef long long ll;

int main(){
    int in;
    char S[1000];
    
    for(int i=0;;i++){
        
        in = getchar();
        
        if(in==EOF){
            S[i]='\0';
            break;
        }else{
            S[i]=(char)in;
        }
    }
    
    for(int k=0;k<27;k++){
        
        bool f = false;
        
        for(int i=0;;i++){
            if('a'<=S[i] && S[i]<='y'){
                S[i]++;
            }else if(S[i]=='z'){
                S[i]='a';
            }
            
            if(i>=3){ // && !('a'<=S[i] && S[i]<='z')){
                if(S[i-3]=='t' && S[i-2]=='h' && S[i-1]=='e')
                    f=true;
            }
            if(i>=4){ // && !('a'<=S[i] && S[i]<='z')){
                if(S[i-4]=='t' && S[i-3]=='h')
                    if((S[i-2]=='i' && S[i-1]=='s') || (S[i-2]=='h' && S[i-1]=='t'))
                        f=true;
            }
            
            if(S[i]=='\0') break;
        }
        
        if(f) break;
    }
    
    for(int i=0;S[i]!='\0';i++)
        printf("%c",S[i]);
    
    return 0;
}

C++: #include<iostream>
#include<cstring>
#include<sstream>
using namespace std;
/*
string text = "hello world";
stringstream ss(text);
string t;
while (ss >> t){
*/
void fin(string a)
{
	a.erase(0,1);
	cout << a << endl;
	return;
}
int main()
{
	string a,b;
	bool fir=false;
	while (cin >> b)
	{
		a.append(" ");
		a.append(b);
		fir = true;
	}
	while (1)
	{
		if (a.find(" the ", 0) != string::npos)
		{
			fin(a); return 0;
		}
		if (a.find(" this ", 0) != string::npos)
		{
			fin(a); return 0;
		}
		if (a.find(" that ", 0) != string::npos)
		{
			fin(a); return 0;
		}
		for (int i = 0; i < a.size(); i++)
		{
			if (a[i] != ' '&&a[i]!='.')a[i] += 1;
			if (a[i]>'z')a[i] = 'a';
		}
	}
}

C++: #include<iostream>
#include<string>
using namespace std;
 
bool valid(string line){
  string t[3] = {"the", "this", "that"};
  for ( int i = 0; i < 3; i++ ){
    if ( line.find(t[i]) != string::npos ) return true;
  }
  return false;
}
 
void move(string &line){
  for ( int i = 0; i < line.size(); i++ ){
    if ( line[i] == 'a' ) line[i] = 'z';
    else if ( 'b' <= line[i] && line[i] <= 'z' ){
      line[i] = (char)(line[i]-1);
    }
  }
}
int main(){
  string line;
  while(1){
    getline(cin, line);
    if ( cin.eof() ) break;
    while(1){
      if ( valid(line) ) {
    cout << line << endl;
    break;
      }
      move(line);
    }
  }
  return 0;
}

C++: #include <iostream>
#include <cmath>
#include <cstdio>
#include <vector>

using namespace std;
string s;
char decrypt[50];
int key,i;

int main(){
    while(getline(cin,s)){
        const char *encrypt = s.c_str();
        while(encrypt[i] != '\0'){
            if(encrypt[i] - encrypt[i+1] == 12){
                key = 't' - encrypt[i];
                break;
            }
            i++;
        }

        i = 0;
        while(encrypt[i] != '\0'){
            if(encrypt[i] <= 'z' && encrypt[i] >= 'a'){
                decrypt[i] = (encrypt[i] - 'a' + key + 26) % 26 + 'a';
            }
            else{
                decrypt[i] = encrypt[i];
            }
            i++;
        }
        while(i <= 50){
            decrypt[i] = '\0';
            i++;
        }
        printf("%s\n", decrypt);
    }
    return 0;
}

C++: #include <cstdio>
#include <cstdlib>
#include <iostream>
#include <string>
#include <cmath>
#include <algorithm>
#include <vector>
#include <queue>
#include <stack>
#include <map>

using namespace std;
typedef long long ll;

int main(){
    int in;
    char S[1000];
    
    gets(S);
    
    while(1){
        
        bool f = false;
        
        for(int i=0;S[i]!='\0';i++){
            if('a'<=S[i] && S[i]<='y'){
                S[i]++;
            }else if(S[i]=='z'){
                S[i]='a';
            }
            
            if(i>=2){
                if(S[i-2]=='t' && S[i-1]=='h' && S[i]=='e')
                    f=true;
            }
            if(i>=3){
                if(S[i-3]=='t' && S[i-2]=='h')
                    if((S[i-1]=='i' && S[i]=='s') || (S[i-1]=='a' && S[i]=='t'))
                        f=true;
            }
        }
        
        if(f) break;
    }
    
    for(int i=0;S[i]!='\0';i++)
        printf("%c",S[i]);
    
    return 0;
}