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 <fstream>
#include <algorithm>
#include <vector>
#include <string>
#include <functional>
#include <array>
#include <stack>
#include <queue>
#include <chrono>
#include <numeric>
#include <memory.h>
#include <map>
#include <math.h>
#include <utility>
#include <set>

#pragma warning(disable:4996)
using namespace std;
#define REP(i,n) for(int i = 0 ; i < n ; ++i)
typedef long long Int;
const double PI = 3.141592653589793238;
const Int INF = 999999999999;
typedef pair<int, int> P;

vector<string> aa;

int main()
{
	string a;
	while (cin >> a){
		aa.push_back(a);
	}

	string c[3] = { "this", "that" , "the"};

	vector<string> nn;
	vector<string> kk;
	for (auto x : aa){
		auto n = x.length();
		if (n == 3){
			kk.push_back(x);
		}
		if (n == 4){
			nn.push_back(x);
		}
	}

	for (auto x : kk){
		auto n1 = x[0] - c[2][0];
		bool f(true);

		for (int i = 1; i < 3; ++i){
			if (n1 != x[i] - c[2][i])
				f = false;
		}

		if (f){
			int i(0);
			for (auto x : aa){
				for (auto y : x){
					if (y == '.'){
						cout << y;
						continue;
					}

					int q = y - 'a';
					if (q - n1 < 0){
						q = 27 - n1;
					}
					else
						q -= n1;

					cout << (char)(q + 'a');
				}
				if (i < aa.size() - 1)
					cout << " ";
				++i;
			}
			cout << endl;
			return 0;
		}
	}

	for (auto x : nn){
		auto n1 = x[0] - c[0][0];
		auto n2 = x[0] - c[1][0];
		bool f(true);
		bool f2(true);

		for (int i = 1; i < 4; ++i){
			if (n1 != x[i] - c[0][i])
				f = false;
			if (n2 != x[i] - c[1][i])
				f2 = false;
		}

		if (f){
			int i(0);
			for(auto x : aa){
				for (auto y : x){
					if (y == '.'){
						cout << y;
						continue;
					}

					int q = y - 'a';
					if (q - n1 < 0){
						q = 27 - n1;
					}
					else
						q -= n1;

					cout << (char)(q + 'a');
				}
				if (i < aa.size()-1)
					cout << " ";
				++i;
			}
			cout << endl;
			return 0;
		}
		else if (f2){
			int i(0);
			for (auto x : aa){
				for (auto y : x){
					if (y == '.'){
						cout << y;
						continue;
					}

					int q = y - 'a';
					if (q - n2 < 0){
						q = 27 - n2;
					}
					else
						q -= n2;

					cout << (char)(q+'a');
				}
				if (i < aa.size() - 1)
					cout << " ";
				++i;
			}
			cout << endl;
			return 0;
		}

	}

	cout << "emd";
	return 0;
}

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

using namespace std;

int main()
{
    string str;
    getline(cin, str);
    for (int shift = 0;; shift++) {
        bool f = false;
        string s(str);
        for (int pos = 0; pos < s.size(); pos++) {
            char c = s.at(pos);
            if (c >= 'a' && c <= 'z') {
                s[pos] = (char)((((int)c - 'a' + shift) % 26) + 'a'); 
            }
        }
        if (s.find("the") != string::npos || s.find("that") != string::npos || s.find("this") != string::npos) {
                cout << s << endl;
                break;
        }
    }
}

C++: #include<iostream>
#include<cstring>
#include<stdio.h>
using namespace std;

int main(){
  char a[100],b[100];
  for(int i;i<100;i++){
    a[i]='\0';
    b[i]='\0';
  }
  gets(a);
  int i=0;
  while(i<26){
    for(int j=0;!(a[j]=='\0');j++){
      if(0x61<=a[j]+i&&a[j]+i<=0x7A)
	b[j]+=i;
      else if(0x61<=a[j]&&a[j]<=0x7A){
	b[j]=a[j]-26+i;
      }
      else if(a[j]==' ')
	b[j]=' ';
      else if(a[j]=='.')
	b[j]='.';
    }
    if(strstr(b,"the")||strstr(b,"this")||strstr(b,"that"))
      break;
    i++;
  }
  for(int k=0;a[k]!='\0';k++)
    cout<<b[k];
  cout<<'\n';
  return 0;
}

C++: #define scanf_s scanf
#define gets_s gets
#include <stdio.h>
#include <string>
#include <iostream>
#include <math.h>
using namespace std;
#define MAX 81
#define _MAX 100
#define ABC 26
int main(void)
{
	int n, s = 0, x, y, r = 0, d;
	char str[MAX];
	while (gets_s(str) != NULL) {
		for (int i = 0; str[i] != '\0'; ++i) {
			if (str[i] - 't' == str[i + 1] - 'h') {
				d = str[i] - 't';
				if ((str[i + 2] - 'a' - d + ABC) % ABC == 'e' - 'a') { break; }
				else if ((str[i + 2] - 'a' - d + ABC) % ABC == 'i' - 'a' && (str[i + 3] - 'a' - d + ABC) % ABC == 's' - 'a') { break; }
				else if ((str[i + 2] - 'a' - d + ABC) % ABC == 'a' - 'a' && (str[i + 3] - 'a' - d + ABC) % ABC == 't' - 'a') { break; }
			}
		}
		for (int i = 0; str[i] != '\0'; ++i) {
			if ('a' <= str[i] && str[i] <= 'z') {
				str[i] = (str[i] - 'a' - d + ABC) % ABC + 'a';
			}
		}
		printf("%s\n", str[i]);
	}
}

C++: #include<cstdio>
#include<iostream>
#include<cstring>
int main(){
    char stl[81];
    char aaaaaataaaaaaaaaari[3][5] = {"this","that","the"};
    int x=0;
    while(1){
        scanf("%c",&stl[x]);
        if(stl[x]==10){
            stl[x] = '\0';
            break;
        }
        x++;
    }
    while(1){
        for(int i=0;;i++){
            if(stl[i]=='\0')
                break;
            if('a'<=stl[i]&&stl[i]<='z')
                stl[i]--;
            if(stl[i]=='a'-1)
                stl[i]='z';

            //printf("%c",stl[i]);

        }//puts("");
        /*for(int i=0;;i++){
            if()
            if(stl[i]=='t'&&stl[i+1]=='h'){
                if(stl[i+2]=='e')
                    goto exit;
                else if(stl[i+2]=='i'&&stl[i+3]=='s')
                    goto exit;
                else if(stl[i+2]=='a'&&stl[i+3]=='t')
                    goto exit;
            }
        }*/
        for(int i=0;i<3;i++)if(strstr(stl,aaaaaataaaaaaaaaari[i])) goto exit;
    }
exit:
    printf("%s\n",stl);
        //a=97
    return 0;
}

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

int checkCaesarChipher(string str1, string str2){
	int a[1000],b[1000];
	bool flag = false;
	
	for(unsigned int i=0 ; i<str1.size()-1 ; i++){
		a[i] = (str1[0] - str1[i] + 26 - 'a') % 26;
		b[i] = (str2[0] - str2[i] + 26 - 'a') % 26;
		if(a[i]==b[i]){
			flag = true;
		}else{
			flag = false;
			break;
		}
	}
	if(flag){
		return (str2[0] - str1[0]);
	}else{
		return 0;
	}
}

int main(){
	string str[400];
	int i=0, ans=0;
	while(cin >> str[i]){
		
		i++;
		//if( str[i-1][str[i-1].size()-1]=='.') break;
	}
	for(int j=0 ; j<i ; i++){
		ans = 0;
		if(str[j].size()==3){
			string hoge1 = "the";
			if(checkCaesarChipher( hoge1 , str[j] )!=0){
				ans = checkCaesarChipher( hoge1 , str[j] );
				break;
			}
		}
		if(str[j].size()==4){
			string hoge2 = "that";
			if(checkCaesarChipher( hoge2 , str[j] )!=0){
				ans = checkCaesarChipher( hoge2 , str[j] );
				break;
			}
			string hoge3 = "this";
			if(checkCaesarChipher( hoge3 , str[j] )!=0){
				ans = checkCaesarChipher( hoge3 , str[j] );
				break;
			}
		}
	}
	if(ans!=0){
		for(int j=0 ; j<i ; j++){
			for(unsigned int k=0 ; k<str[j].size() ; k++){
				if(str[j][ str[j].size()-1] != '.'){
					str[j].at(k) -= ans;
				}
			}
			if(j==i-1) cout << str[j] << endl;
			else cout << str[j] << " ";
		}
	}
	return 0;
}