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 <cstdio>
#include <vector>
#include <algorithm>
#include <regex>
#include <cctype>
#include <string>
using namespace std;

vector<string> v;

vector<string> split(string&& s, regex&& pattern) {
    sregex_token_iterator first(s.begin(), s.end(), pattern, -1);
    sregex_token_iterator last;
    return(vector<string>(first, last));
}

bool cheser() {
    for(int r = 1; r <= 26; r++) {
        bool found = false;
        for(int c = 0; c < v.size(); c++) {
            for(int k = 0; k < v[c].length(); k++) {
                if(!isalpha(v[c][k])) continue;
                int now = v[c][k] - 'a';
                now = (now+1)%26;
                v[c][k] = 'a' + now;
            }
            if(v[c] == "the" || v[c] == "this" || v[c] == "that") found = true;
        }
        if(found) return(true);
    }
    return(false);
}

int main(void) {
    string input;
    while(getline(cin, input)) {
        v = split(move(input), regex(" "));
        cheser();
        for(int r = 0; r < v.size(); r++) {
            cout << v[r];
            if(r == v.size() - 1) cout << endl;
            else                  cout << " ";
        }
    }
    
    return(0);
}

C++: #include <iostream>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <algorithm>
#include <stdlib.h>
#include <vector>

using namespace std;


int main(){

	string line;

	while(getline(cin, line)){

		string str[80], ans[80];
		int count = 0;
		int flag = 0;
		int slide;

		//???????????????
		/*
		string temp;
		for(int i=0 ; i<line.size()-1 ; i++){
			temp += line[i];
		}
		line = temp;
		*/

		//???????????????????????¨???????´?
		for(int i=0 ; i<line.size() ; i++){
			if(line[i] == ' '){
				count++;
			}else{
				str[count] += line[i];
				ans[count] = str[count];
			}
		}
		count++;


		for(int i=1 ; i<=26 ; i++){
			for(int j=0 ; j<count ; j++){
				for(int k=0 ; k<str[j].size() ; k++){
					if(str[j][k] != '.'){
						str[j][k]++;
						if(str[j][k] > 'z'){
							str[j][k] = str[j][k] - 'z' + 'a' -1;
						}
					}
					if(str[j][k] == 'h' && str[j][k-1] == 't'){
						flag = 1;
						slide = i;
						break;
					}
				}

				/*
				if(str[j] == "this" || str[j] == "the" || str[j] == "that"
						|| str[j] == "this." || str[j] == "the." ||str[j] == "that."){
					flag = 1;
					slide = i;
					break;
				}
				*/
			}
			if(flag == 1)break;
		}

		for(int i=0 ; i<count ; i++){
			for(int j=0 ; j<ans[i].size() ; j++){
				if(ans[i][j] != '.'){
					if((ans[i][j] + slide) > 'z' ){
						ans[i][j] = ans[i][j] - 'z' + 'a' + slide -1;
					}else{
						ans[i][j] = ans[i][j] + slide ;
					}
				}
			}
		}

		for(int i=0 ; i<count ; i++){
			cout << ans[i] << ' ';
		}
		cout << ans[count] << endl;

	}
	return 0;
}

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

std::string decrypto(std::string str) {
    using namespace std;
    regex pattern(".*(the|this|that).*");
    smatch sm;
    for (int c = 0; c < 'z' - 'a' + 1; ++c) {
        for (size_t i = 0; i < str.size(); ++i) {
            if ('a' <= str[i] && str[i] <= 'z') {
                if (str[i] == 'z') {
                    str[i] = 'a';
                } else {
                    str[i] += 1;
                }
            }
        }
        //if (regex_match(str, sm, pattern)) {
        if (str.find( "the" ) != string::npos || str.find( "this" ) != string::npos || str.find( "that" ) != string::npos) {
            return str;
        }
    }
    return string("");
}

int main() {
    std::string str;
    while (std::getline(std::cin, str)) {
        std::cout << decrypto(str) << std::endl;
    }
}

C++: #include <iostream>
#include <string>
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(s[i] == 'z')
							s[i] = 'a';
						else if(s[i] >= 'a' && s[i] <= 'z')
							s[i]++;
					}
				}
		cout << s << endl;		
	}
}

C++: #include <bits/stdc++.h>
using namespace std;
int main()
{
    string s;
    int k,i,n,x;
    char c;
    while(getline(cin,s)){
        n=s.length();
        for(i=0;i<n;i++){
            if(islower(s[i])){
                k=s[i]-'a';
                k=k-4;
                if(k<0) k=k+26;
                c='a'+k;
                cout<<c;
            }
            else cout<<s[i];
        }
        cout<<endl;
    }
}

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

int main(){
	
	string str, str1;

	while(getline(cin, str)){
		for(int i=0; i<26; i++){
			for(int j=0; j<str.length(); j++){
				if(str[j] == ' ' || str[j] == '.') continue;
				if(str[j] == 'z') str[j] = 'a';
				else{
					str[j] = str[j] + 1;
				}
			}
			
			str1 = "";
			for(int j=0; j<str.length(); j++){
				if(str[j] != ' ') str1 += str[j];
				else{
					if(str1 == "the" || str1 == "this" || str1 == "that"){
						cout << str << endl;
						return 0;
					}
					else str1 = "";
				}
			}
		}
	}

	return 0;
	
}

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

int main(int argc, char *argv[]){
  char c[26];
  for (int i = 0; i < 26; i++) {
    c[i] = 'a' + i;
  }
  vector<string> vs;
  string s;
  string ans[] = {"this", "that", "the"};
  vector<string> tmp;
  while(cin >> s)vs.push_back(s);
  vs[vs.size() - 1].pop_back();
  for (int k = 0; k < 26; k++) {
    tmp = vs;
    for (int i = 0; i < vs.size(); i++) {
      for (int j = 0; j < vs[i].length(); j++) {
        tmp[i][j] = c[(vs[i][j] - 'a' + k) % 25];
      }
    }
    for (int i = 0; i < 3; i++) {
      for (int j = 0; j < tmp.size(); j++) {
        if(tmp[j] == ans[i]){k = 50, i = 10, j = 1000;}
      }
    }
  }
  for (int i = 0; i < tmp.size(); i++) {
    std::cout << tmp[i];
    if(i == tmp.size() - 1)std::cout << "." << std::endl;
    else std::cout << " ";
  }
  return 0;
}

C++: #include<iostream>
#include<string>
#include<sstream>
#include<vector>
using namespace std;
#define REP(i, j) for(int i = 0; i < j; i++)
#define FOR(i, j, k) for(int i = j; i < k; i++)
const int N = 30;

bool isOK(vector<string> v){
    REP(i, v.size()) if(v[i] == "the" || v[i] == "this" || v[i] == "that") return true;
    return false;
}

int main(){
    string str;
    while(getline(cin, str)){
        str = str.substr(0, str.length());
        string tmp;
        stringstream ss(str);
        vector<string> v;
        while(ss >>tmp) v.push_back(tmp);
        REP(z, N){
            REP(i, v.size()) REP(j, v[i].length()) v[i][j] = ++v[i][j] <= 'z'? v[i][j] : 'a';
            if(isOK(v)){
                cout <<v[0];
                FOR(i, 1, v.size()) cout <<" " <<v[i];
                cout <<'.' <<endl;
                break;
            }
        }
    }
    return 0;
}