Go: package main

import (
	"bufio"
	"os"
	"strings"
	"fmt"
)

var scanner = bufio.NewScanner(os.Stdin)

func nextString() string {
	scanner.Scan()
	return scanner.Text()
}

func cipher(text string, direction int, int_shift int) string {
	shift, offset := rune(int_shift), rune(26)
	runes := []rune(text)
	for index, char := range runes {
		switch direction {
		case 1:
			if char >= 'a' && char <= 'z'-shift || char >= 'A' && char <= 'Z'-shift {
				char = char + shift
			} else if char > 'z'-shift && char <= 'z' || char > 'Z'-shift && char <= 'Z' {
				char = char + shift - offset
			}
		case -1:
			if char >= 'a'+shift && char <= 'z' || char >= 'A'+shift && char <= 'Z' {
				char = char - shift
			} else if char >= 'a' && char < 'a'+shift || char >= 'A' && char < 'A'+shift {
				char = char - shift + offset
			}
		}
		runes[index] = char
	}
	return string(runes)
}

func main() {
	for {
		infos := strings.Split(nextString(), " ")
		plain := make([]string, len(infos))
		if len(infos) == 0 {
			break
		}
		// println(infos)
		Decryption:
			for i := 0; i < 26; i++ {
				for j := range infos {
					plain[j] = cipher(infos[j], 1, i)
				}
				for j := range plain {
					if plain[j] == "this" || plain[j] == "that" || plain[j] == "the" {
						break Decryption
					}
				}
			}
			fmt.Println(strings.Join(plain, " "))
	}
}

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

typedef long long int ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<pair<int, int> > vii;
#define rrep(i, m, n) for(int (i)=(m); (i)<(n);  (i)++)
#define erep(i, m, n) for(int (i)=(m); (i)<=(n); (i)++)
#define  rep(i, n)    for(int (i)=0; (i)<(n);  (i)++)
#define rrev(i, m, n) for(int (i)=(n)-1; (i)>=(m); (i)--)
#define erev(i, m, n) for(int (i)=(n); (i)>=(m); (i)--)
#define  rev(i, n)    for(int (i)=(n)-1; (i)>=0; (i)--)
#define vrep(i, c)    for(__typeof((c).begin())i=(c).begin(); i!=(c).end(); i++)
#define  ALL(v)       (v).begin(), (v).end()
#define mp            make_pair
#define pb            push_back
template<class T, class S> inline bool minup(T& m, S x){ return m>(T)x ? (m=(T)x, true) : false; }
template<class T, class S> inline bool maxup(T& m, S x){ return m<(T)x ? (m=(T)x, true) : false; }

const int    INF = 1000000000;
const ll     MOD = 1000000007LL;
const double EPS = 1E-12;

template<typename T> ostream& operator << (ostream& r, const vector<T> t){vrep(v,t)r<<*v<<(v+1==t.end()?"":" ");return r;}
template<typename T> ostream& operator << (ostream& r, const pair<vector<T>, int> p){int n=p.second;minup(n,p.first.size());rep(i,n-1)r<<p.first[i]<<' ';r<<p.first[n-1];return r;}
template<typename T> ostream& operator << (ostream& r, const pair<T*, int> p){int n=p.second-1;rep(i,n)r<<p.first[i]<<' ';return r<<p.first[n];}
template<typename T, size_t S> ostream& operator << (ostream& r, const T (&a)[S]){rep(i,S-1)r<<a[i]<<' ';return r<<a[S-1];}

string str;
vector<string> res;

int main()
{
  while(cin >> str) res.pb(str);

  bool ok = false;
  rep(k, 26){
    vrep(v, res) rep(i, v->size()) if((*v)[i] >= 'A' && (*v)[i] <= 'z') (*v)[i] = 'a' + ((*v)[i] + 1) % 26;
    vrep(v, res) if(*v == "the" || *v == "this" || *v == "that") ok = true;
    if(ok){
      cout << res << endl;
      break;
    }
  }

  /*
  while(getline(cin, str)){
    vector<string> s;
    istringstream stream(str);
    while(getline(stream, str, ' ')) s.pb(str);
    bool ok = false;
    rep(k, 26){
      vrep(v, s) rep(i, v->size()) if((*v)[i] >= 'A' && (*v)[i] <= 'z') (*v)[i] = 'a' + ((*v)[i] + 1) % 26;
      vrep(v, s) if(*v == "the" || *v == "this" || *v == "that") ok = true;
      if(ok){
        cout << s << endl;
        break;
      }
    }
  }
  */
 return 0;
}

C++: #include<stdio.h>
#include<iostream>
#include<math.h>
#include<string>
using namespace std;
int main(){
	
	char s[100];
	while(cin.getline(s,100)){
		for(int i=0;s[i]!='\0';i++){
			if((s[i]-s[i+1]=='t'-'h')&&(((s[i+1]-s[i+2]=='h'-'i')&&(s[i+2]-s[i+3]=='i'-'s'))||(s[i+1]-s[i+2]=='h'-'e')||((s[i+1]-s[i+2]=='h'-'a')&&(s[i+2]-s[i+3]=='a'-'t')))){
				for(int j=0;s[j]!='\0';j++){
					if((s[j]!=' ')&&(s[j]!='.')){
						if(s[j]+'t'-s[i]-'a'<0){
							putchar('z'-'a'+s[j]+'t'-s[i]);
						}else{
							putchar(s[j]+'t'-s[i]);
						}
					}else{
						putchar(s[j]);
					}
				}cout<<endl;
				break;
			}
		}
	}
}

C++: 

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cmath>
#include<math.h>
#include<string>
#include<string.h>
#include<stack>
#include<queue>
#include<vector>
#include<utility>
#include<set>
#include<map>
#include<stdlib.h>
#include<iomanip>

using namespace std;

#define ll long long
#define ld long double
#define EPS 0.0000000001
#define INF 1e9
#define MOD 1000000007
#define rep(i,n) for(i=0;i<n;i++)
#define loop(i,a,n) for(i=a;i<n;i++)
#define all(in) in.begin(),in.end()
#define shosu(x) fixed<<setprecision(x)

typedef vector<int> vi;
typedef pair<int,int> pii;

int main(void) {
  int i,j,k;
  string s;
  char ans[6][10]={"the","the.","this","this.","that","that."};
  while(getline(cin,s)){
    int n=0;
    rep(i,s.size())if(s[i]==' ')n++;
    n++;
    vector<string> word(n);
    i=0;
    rep(j,n){
      while(s[i]!=' '&&s[i]!='\0')
	word[j].push_back(s[i]),i++;
      i++;
    }
    rep(k,26){
      bool c=false;
      rep(i,n)rep(j,word[i].size())
	if(word[i][j]=='z')word[i][j]='a';
	else if(word[i][j]<='z' && word[i][j]>='a')
	  word[i][j]=word[i][j]+1;
      rep(i,n)rep(j,6)
	if(word[i]==ans[j]){
	  c=true;
	}
      if(c){
	rep(i,n){
	  if(i)cout<<" ";
	  cout<<word[i];
	}
	cout<<endl;
	break;
      }
    }
  }
}

C++: #include <iostream>
#include <cstdio>
#include <string>
using namespace std;
int main() {
	string str;
	while(getline(cin, str)) {
		int n = 't' - str[0];
		for(int i = 0; str[i] != '\0'; i++) {
			if(('a' <= str[i])&&(str[i] <= 'z')) {
				str[i] += n;
				if(str[i] > 'z') {
					str[i] -= 'z' + 'a';
				}
			}
		}
		cout << str << endl;
	}
	return 0;
}

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

int main() {
  string str,s,newstr;
  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++) {
      if(seq[i].size() == 4) {// ??that.
	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] == 'i' && decode[3] == 's') {
	    key = j;
	    break;
	  }
	  if(decode[0] == 't' && decode[1] == 'h' && decode[2] == 'a' && decode[3] == 't') {
	    key = j;
	    break;
	  }
	}
      }
      if(key!=100) break;
    }

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