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<cstdio>
#include<cctype>
#include<cstring>
using namespace std;
int main(){
    int f = 0;
    while(1){
        char a;
        char str[100] = {0};
        scanf("%[^\n]s",str);
        for(int i = 0;i <= 25; i++){
            for(int j = 0;j < strlen(str); j++){
                if(str[j] == '\n' || str[j] == '.')continue;
                str[j] += 1;
                }
                for(int k = 0;k < strlen(str); k++){
                    if(str[k] == 't' &&  str[k+1] == 'h' && str[k+2] == 'e')goto hoge;
                    if(str[k] == 't' &&  str[k+1] == 'h' && str[k+2] == 'i' && str[k+3] == 's')goto hoge;
                    if(str[k] == 't' &&  str[k+1] == 'h' && str[k+2] == 'a' && str[k+3] == 't')goto hoge;
            }
        }
        for(int i = 0;i < strlen(str); i++){
            if(str[i] == '\n' || str[i] == '.')continue;
            str[i] -= 25;
        }

        for(int i = 0;i <= 25; i++){
            for(int j = 0; j< strlen(str); j++){
                if(str[j] == '\n' || str[j] == '.')continue;
                str[j] -= 1;
            }
            for(int k = 0;k < strlen(str); k++){
                    if(str[k] == 't' &&  str[k+1] == 'h' && str[k+2] == 'e')goto hoge;
                    if(str[k] == 't' &&  str[k+1] == 'h' && str[k+2] == 'i' && str[k+3] == 's')goto hoge;
                    if(str[k] == 't' &&  str[k+1] == 'h' && str[k+2] == 'a' && str[k+3] == 't')goto hoge;
            }
        }

        hoge:

        for(int i = 0;i < strlen(str)-1; i++)if(str[i] == 46)str[i] = ' ';
        printf("%s\n",str);
        //for(int i = 0;i < strlen(str); i++)str[i] = 0;
        getchar();
        if(getchar() == EOF)return 0;
    }
    return 0;
}

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

using namespace std;
int main(){
	string str1;
	int i, j, n = 0;
	while(getline(cin, str1)){
		bool change = false;
		for(i = 0;i < 28;i++){
			for(j = 0;j < str1.size();j++){
				if(str1[j] != ' ' && str1[j] != '.'){
					if(str1[j] == 'a'){
						str1[j] = 'z';
					}
					else str1[j] -= 1;
				}
			}
			for(j = 0;j+3 < str1.size();j++){
				if(str1[j] == 't' && str1[j+1] == 'h'){
					if(str1[j+2] == 'e' || (str1[j+2] == 'i' && str1[j+3] == 's') || (str1[j+2] == 'a' && str1[j+3] == 't')){
						n = i + 1;
						change = true;
						break;
					}
				}
			}
			if(change) break;
		}	
		for(i = 0;i < str1.size();i++){
			cout << str1[i];
		}
		
	}


	return 0;
}

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

using namespace std;

int main(int argc, const char * argv[])
{
    int shift = 1, i=0;
    string in,out;
    getline(cin,in);
    out = in;
    do {
        for (i=0; i<in.length(); i++) {
            if (in[i]!=' '&&in[i]!='.') {
                out[i] = ((in[i] - 'a' + shift) % 26) + 'a';
            }
        }
        if (out.find("the")!=std::string::npos||out.find("that")!=std::string::npos||out.find("this")!=std::string::npos) {
            break;
        }
        else
            shift++;
    } while (shift<=25);
    
    cout<<out<<endl;
    return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<string>
#include<cstdio>
#include<cstring>
using namespace std;
int main(){
  string str;
  char s[256];
  int w = 0;
  while(scanf("%c",&s[0]) != EOF){
    do {
      w++;
      scanf("%c",&s[w]);
    }while(s[w] != '\n');
    while(1){
      s[w] = '\0';
    
      for(int i=0;i<w;i++){
	if(s[i] != ' ' && s[i] != '.'){
	  s[i]++;
	  if(s[i]>'z')s[i] = s[i] - 'z' + 'a' - 1;
	}
      }
      if(strstr(s,"the") != NULL)break;
      if(strstr(s,"that") != NULL)break;
      if(strstr(s,"this") != NULL)break;
    }
    printf("%s\n",s);
    memset( s , 0 , sizeof(s) );
  }
}

C++: #include <algorithm>
#include <iostream>
#include <cstdio>
#include <map>
#include <numeric>
#include <set>
#include <sstream>
#include <string>
#include <vector>
#include <queue>
#include <string.h>
using namespace std;

#define ISEQ(c) (c).begin(), (c).end()
typedef long long ll;

int main() {
  char s[90];
  while (fgets(s, 81, stdin) != 0) {
    for (int i = 0; i < 26; i++) {
      for (int j = 0; j < strlen(s); j++) {
	if (isalpha(s[j])) {
	  if (s[j] == 'z') s[j] = 'a';
	  else s[j]++;
	}
      }
      if (strstr(s, "the") != NULL or strstr(s, "this") != NULL or strstr(s, "that") != NULL) break;
    }
    printf("%s\n", s);
  }
}

C++: #include <vector>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <algorithm>
#include <utility>
#include <functional>
#include <sstream>
#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <climits>
#include <fstream>
using namespace std;
inline int toInt(string s) { int v; istringstream sin(s); sin >> v; return v;}
template<class T> inline string toStr(T x) { ostringstream sout; sout << x; return sout.str();}
typedef vector<int> vi;
typedef vector<vi>  vvi;
typedef vector<string> vs;
typedef pair<int, int> pii;
typedef long long ll;
#define ALL(a) (a).begin(),(a).end()
#define RALL(a) (a).rbegin(),(a).rend()
#define FOR(i,a,b) for(int i=(a);i<=(b);++i)
#define REP(i,n) FOR(i,0,(n)-1)
const double EPS = 1e-12;
const double PI = acos(-1.0);
const int INF = INT_MAX/10;
 
int main() {
    string s;
    while(getline(cin, s)) {
        REP(i, 26) {
            REP(j, s.length()) {
                if('a' <= s[j] && s[j] <= 'z') {
                    s[j]++;
                    if('z' < s[j]) {
                        s[j] -= 26;
                    }
                }
            }
 
            if(s.find("the") != string::npos) {
                cout << s << endl;
                goto next;
            } else if(s.find("this") != string::npos) {
                cout << s << endl;
                goto next;
            } else if(s.find("that") != string::npos) {
                cout << s << endl;
                goto next;
            }
        }
 
        next:;
    }
 
    return 0;
}