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 <string.h>
#include <string>
#include <stdio.h>
using namespace std;
int main() {
	string w[3]={"the","this","that"},st;
	int wn[3]={3,4,4},k,i,j,s,f;
	while(true) {
    k=0; 
	getline(cin,st);
	while(k<st.size()) {
		for (i=0;i<3;i++) {
			s=0; f=0;
			if (st.size()<k+wn[i]) break;
			for (j=0;j<wn[i]-1;j++) if ((w[i][j]-w[i][j+1])==(st[k+j]-st[k+j+1])) s++;
			if (s==wn[i]-1)  { f=1; i=5;}
		}
		if (f==1) break;
		for (k;st[k]>='a' && st[k]<='z';k++);
		k++;
	}
	if (f==0) cout << st; else {
		for (i=0;i<st.size();i++) 
			if ((st[i]>='a' && st[i]<='z')) cout << (char)(((st[i]-st[k]+'t')-97+26) % 26 + 97) ; 
		    else cout << st[i];
	}
	cout << endl;
	}
	return 0;
	}

C++: #include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <stack>
#include <cmath>
using namespace std;

#define REP(i, n) for(int i = 0;i < n;i++)
#define REPR(i, n) for(int i = n;i >= 0;i--)
#define FOR(i, m, n) for(int i = m;i < n;i++)
#define llong long long

int main() {
  char *a = (char*)malloc(sizeof(char)*82);
  size_t l = 0;
  while (getline(&a, &l, stdin) != EOF) {
    while(1) {
      int q = 0;//-1..out, 0..space, 1..t, 2..th, 3..the, 4...thi, 5..this, 6..tha, 7..that, 8..ok
      REP(j , (int)l-1) {
	if(a[j] == 'z') a[j] = 'a';
	else if(a[j] >= 'a' && a[j] < 'z') a[j]++;
      }
      REP(j , (int)l-1) {
	switch(q){
	case -1:
	  if(a[j] == ' ') q = 0;
	  break;
	case 0:
	  if(a[j] == 't') q = 1;
	  else q = -1;
	  break;
	case 1:
	  if(a[j] == 'h') q = 2;
	  else q = -1;
	  break;
	case 2:
	  if(a[j] == 'e') q = 3;
	  else if(a[j] == 'i') q = 4;
	  else if(a[j] == 'a') q = 6;
	  else q = -1;
	  break;
	case 3:
	  if(a[j] > 'z' || a[j] < 'a') q = 8;
	  else q = -1;
	  break;
	case 4:
	  if(a[j] == 's') q = 5;
	  else q = -1;
	  break;
	case 5:
	  if(a[j] > 'z' || a[j] < 'a') q = 8;
	  else q = -1;
	  break;
	case 6:
	  if(a[j] == 't') q = 7;
	  else q = -1;
	  break;
	case 7:
	  if(a[j] > 'z' || a[j] < 'a') q = 8;
	  else q = -1;
	  break;
	}
      }
      if(q == 8) break;
    }
    printf("%s",a);
    /*    REP(i , (int)l-1) {
      printf("%c",a[i]);
    }*/
  }
  return 0;
}

C++: #include<stdio.h>
#include<iostream>
#include<math.h>
#include<string>
using namespace std;
int main(){
	
	char s[1000];
	while(cin.getline(s,1000)){
		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]+1);
						}else{
							putchar(s[j]+'t'-s[i]);
						}
					}else{
						putchar(s[j]);
					}
				}cout<<endl;
				break;
			}
		}
	}
}

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

using namespace std;

int main(int argc, char *argv[]) {
  string str;
  vector<string> result;
  while (getline(cin, str)) {
    while (true) {
      if (str.find(" this ") != string::npos ||
          str.find(" that ") != string::npos ||
          str.find(" the ") != string::npos)
        break;
      else
        for (int i = 0; i < str.size(); i++)
          if ('a' <= str[i] && str[i] <= 'z') {
            if (str[i] == 'a')
              str[i] = 'z';
            else
              str[i]--;
          }
    }
    result.push_back(str);
  }

  for (int i = 0; i < result.size(); i++)
    cout << result[i] << endl;
  return 0;
  }

C++: #include <cstdio>
#include <cstdlib>
#include <iostream>
#include <string>
#include <cmath>
#include <algorithm>
#include <vector>
#include <queue>
#include <stack>
#include <map>

using namespace std;
typedef long long ll;

int main(){
    int in;
    char S[1000];
    
    S[0]=' ';
    
    for(int i=1;;i++){
        
        in = getchar();
        
        if(in==EOF){
            S[i]='\0';
            break;
        }else{
            S[i]=(char)in;
        }
    }
    
    for(int k=0;;k++){
        
        bool f = false;
        
        for(int i=1;S[i]!='\0';i++){
            if('a'<=S[i] && S[i]<='y'){
                S[i]++;
            }else if(S[i]=='z'){
                S[i]='a';
            }
            
            if(i>=2){
                if(S[i-2]=='t' && S[i-1]=='h' && S[i]=='e')
                    f=true;
            }
            if(i>=3){
                if(S[i-3]=='t' && S[i-2]=='h')
                    if((S[i-1]=='i' && S[i]=='s') || (S[i-1]=='a' && S[i]=='t'))
                        f=true;
            }
        }
        
        if(f) break;
    }
    
    for(int i=1;S[i]!='\0';i++)
        printf("%c",S[i]);
    
    return 0;
}

C++: #include <iostream>
#include <stdio.h>
#include <string>
#include <queue>
#include <cmath>
#include <stack>

#define int64 long long int

using namespace std;

char * caesar(char *);

int main()
{
	int i, c;
	char str[128];
	
	while(1){
		for(i=0; ; i++){
			c = getchar();
			if(c == '\n' || c == EOF) break;
			str[i] = c;
		}
		str[i] = 0;
		cout << caesar(str) << '\n';

		if(c == EOF) break;
	}

	return 0;
}

char * caesar(char *str){
	int len, i;
	len = strlen(str);
	while(1){
		for(i=0; i<len; i++){
			if(str[i] >= 'b' && str[i] <= 'z')
				str[i]--;
			else if(str[i] == 'a')
				str[i] = 'z';
		}
		for(i=0; i<len; i++){
			if(str[i] == 't' && str[i+1] == 'h'){
				if(str[i+2] == 'e' ||
					(str[i+2] == 'i' && str[i+3] == 's') ||
					(str[i+2] == 'a' && str[i+3] == 't'))
					return str;
			}
		}
	}
	return 0;
}

C++: require("fs").readFileSync("/dev/stdin","utf8").split('\n').map(function(i){for(s=26;s--;)r=i.replace(/[a-z]/g,function(j){return j.fromCharCode((j.charCodeAt(0)-97+s)%26+97)}),r.match(/th(e|is|at)/)?console.log(r):0})

C++: #include<stdio.h>
#include<iostream>
#include<math.h>
#include<string>
using namespace std;
int main(){
	
	char s[1000];
	while(cin.getline(s,1000)){
		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]!='.')&&(s[j]!='\n')){
						putchar((s[j]+'t'-s[i]-'a'+26)%26+'a');
					}else{
						putchar(s[j]);
					}
				}cout<<endl;
				break;
			}
		}
	}
	return 0;
}