Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

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 scanner.Scan() {
		infos := strings.Split(scanner.Text(), " ")
		plain := make([]string, len(infos))
		// fmt.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 <iostream>
#include <cstdio>
#include <stdio.h>
#include <string>

using namespace std;
static const int MAXV = 81;

bool hantei(char data[]);
void irekae(char data[]);

int main() {
  while(!feof(stdin)) {
    char data[MAXV];
    if(fgets(data, sizeof(data), stdin)==NULL) break;
    while(!hantei(data))
      irekae(data);
    printf("%s", data);
  }
}

bool hantei(char data[]) {
  if(strstr(data, "the")) return 1;
  if(strstr(data, "this")) return 1;
  if(strstr(data, "that")) return 1;
  return 0;
}

void irekae(char data[]) {
  for(int i=0;data[i]!=0;i++) {
    if(data[i]>='a' && data[i]<='z') {
      if(data[i]=='z')data[i]='a';
      else data[i]++;
    }
  }
}

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

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

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

int main(){
	string str[1000];
	int k = 0;
	int zure[1000];
	bool flag[1000] = {false};
	while(getline(cin, str[k])){
		for(int j = 0; j < 26; j++){
			for(int i = 0; i < str[k].size()-2; i++){
				if(str[k][i] == 't'+j && str[k][i+1] == 'h'+j && str[k][i+2] == 'e'+j){
					zure[k] = j;
					flag[k] = true;
					break;
				}
			}
			if(flag[k] == true){
				k++;
				break;
			}
			for(int i = 0; i < str[k].size()-3; i++){
				if(str[k][i] == 't'+j && str[k][i+1] == 'h'+j && str[k][i+2] == 'i'+j && str[k][i+3] == 's'+j){
					zure[k] = j;
					flag[k] = true;
					break;
				}
			}
			if(flag[k] == true){
				k++;
				break;
			}
			for(int i = 0; i < str[k].size()-3; i++){
				if(str[k][i] == 't'+j && str[k][i+1] == 'h'+j && str[k][i+2] == 'a'+j && str[k][i+3] == 't'+j){
					zure[k] = j;
					flag[k] = true;
					break;
				}
			}
			if(flag[k] == true){
				k++;
				break;
			}
		}
	}
	for(int j = 0; j < k; j++){
		for(int i = 0; i < str[j].size(); i++){
			if(str[j][i] >= 'a' && str[j][i] <= 'z'){
				str[j][i] = str[j][i]-zure[j];
				if(str[j][i] < 'a'){
					str[j][i] = str[j][i]+26;
				}
			}
		}
		cout << str[j] << endl;
	}
}

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

//#define int long long
#define reps(i,s,n) for(int (i)=(s);(i)<(n);++(i))
#define rep(i,n) reps(i,0,n)
#define rept(i,n) rep(i,(n)+1)
#define repst(i,s,n) reps(i,s,(n)+1)
#define reprt(i,n,t) for(int (i)=(n);(i)>=(t);--(i))
#define repr(i,n) reprt(i,n,0)
#define each(itr,v) for(auto &(itr):(v))
#define all(c) (c).begin(),(c).end()
#define rall(c) (c).rbegin(),(c).rend()
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define tmax(x,y,z) max(x,max(y,z))
#define tmin(x,y,z) min(x,min(y,z))
#define chmin(x,y) x=min(x,y)
#define chmax(x,y) x=max(x,y)
#define ln '\n'
#define bln(i,n) (((i)==(n)-1)?'\n':' ')
#define dbg(x) cout<<#x" = "<<(x)<<ln<<flush
#define dbga(x,n) {cout<<#x" : ";for(int (i)=0;i<(n);++i){cout<<((x)[i])<<(i==((n)-1)?'\n':' ')<<flush;}}
#define zero(a) memset(a,0,sizeof(a))
#define unq(a) sort(all(a)),a.erase(unique(all(a)),a.end())

typedef complex<double> P;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<string> vst;
typedef vector<pii> vpii;
typedef vector<pll> vpll;
typedef vector<vector<int> > mat;

const ll inf = (ll)1e9+10;
const ll linf = (ll)1e18+10;
const ll mod = (ll)(1e9+7);
const int dx[] = {0, 1, 0, -1};
const int dy[] = {1, 0, -1, 0};
const int ddx[] = {0, 1, 1, 1, 0, -1, -1, -1};
const int ddy[] = {1, 1, 0, -1, -1, -1, 0, 1};
const double eps = 1e-10;

ll mop(ll a,ll b,ll m=mod) {ll r=1;a%=m;for(;b;b>>=1){if(b&1)r=r*a%m;a=a*a%m;}return r;}
ll gcd(ll a,ll b) {return b?gcd(b,a%b):a;}
ll lcm(ll a,ll b) {return a*b/gcd(a,b);}
bool ool(int x,int y,int h,int w) {return((x<0)||(h<=x)||(y<0)||(w<=y));}
bool deq(double a,double b) {return abs(a-b)<eps;}

struct oreno_initializer {
	oreno_initializer() {
		cin.tie(0);
		ios::sync_with_stdio(0);
	}
} oreno_initializer;

// ━━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…
// .｡.:( ^ω^)・ﾟ＋.｡.:( ^ω^)・ﾟ＋.｡.:( ^ω^)・ﾟ＋.｡.:( ^ω^)・ﾟ＋.｡.:( ^ω^)・ﾟ＋
// ・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・

typedef string::const_iterator S;
string s;

bool ok(S &i, S &e) {
	if (i==e) return 0;
	string t;
	while (*i!=' ') t.pb(*i), i++;
	if (t=="the" || t=="this" || t=="that") return 1;
	return ok(++i,e);
}

signed main() {
	getline(cin,s);
	s.pb(' ');
	rep(i,26) {
		S b = s.begin(), c = s.end();
		if (ok(b,c)) return cout << s << ln, 0;
		rep(j,s.size()) if ('a'<=s[j] && s[j]<='z') {
			s[j]++;
			if (s[j]>'z') s[j] = 'a';
		}
	}
}

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

int main()
{
    string s;
    while(getline(cin, s))
    {
        while(s.find("this")==s.npos && s.find("that") == s.npos && s.find("the") == s.npos)
        {
            for(int i = 0; i <(int) s.size(); i++)
            {
                if(s[i] > 'z' || s[i] < 'a')
                    continue;
                if(s[i] != 'z')
                    s[i]++;
                else
                    s[i] = 'a';
            }
        }
        cout<<s<<endl;
    }
}