Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

func main() {
	for scanner.Scan() {
		var result string
		line := scanner.Text()
		key := make(map[string]string)

		var i int32
		for ; i < 52; i++ {
			makeKey(key, i)
			result = decode(key, line)

			if strings.Contains(result, "the") {
				break
			} else if strings.Contains(result, "this") {
				break
			} else if strings.Contains(result, "that") {
				break
			}
		}

		fmt.Println(result)
	}
}

func makeKey(key map[string]string, shift int32) {
	for i := 'a'; i <= 'z'; i++ {
		cipher := (i + shift)
		if cipher > 'z' {
			cipher = cipher%'z' + 'a' - 1
		} else if cipher < 'a' {
			cipher = cipher + ('z' - 'a') + 1
		}
		key[string(i)] = string(cipher)
	}
}

func decode(key map[string]string, cipher string) string {
	var result string
	for _, v := range cipher {
		if key[string(v)] != "" {
			result += key[string(v)]
		} else {
			result += string(v)
		}
	}
	return result
}

C++: #include<cstdio>
#include<cctype>
#include<cstring>
char str[1000000] = {0};
using namespace std;
int main(){
    int f = 0;
    while(scanf("%[^\n]",str)!=EOF){
        getchar();
        for(int i = 0;i <= 25; i++){
            for(int j = 0;j < strlen(str); j++){
                if(str[j] == ' ' || str[j] == '.')continue;
                str[j]++;
                if(str[j] > 122)str[j] = str[j]-26;
            }
            for(int j = 0;j < strlen(str); j++){
                if(str[j] == 't' && str[j+1] == 'h' && str[j+2] == 'e')goto hoge;
                if(str[j] == 't' && str[j+1] == 'h' && str[j+2] == 'i' && str[j+3] == 's')goto hoge;
                if(str[j] == 't' && str[j+1] == 'h' && str[j+2] == 'a' && str[j+3] == 't')goto hoge;
            }
        }
        for(int i = 0;i < strlen(str); i++){
            if(str[i] == ' ' || str[i] == '.')continue;
            str[i] -= 25;
        }
        for(int i = 0;i <= 25; i++){
            for(int j = 0;j < strlen(str); j++){
                if(str[j] == ' ' || str[j] == '.')continue;
                str[j]--;
                if(str[j] < 97)str[j] = str[j]+25;
            }
            for(int j = 0;j < strlen(str); j++){
                if(str[j] == 't' && str[j+1] == 'h' && str[j+2] == 'e')goto hoge;
                if(str[j] == 't' && str[j+1] == 'h' && str[j+2] == 'i' && str[j+3] == 's')goto hoge;
                if(str[j] == 't' && str[j+1] == 'h' && str[j+2] == 'a' && str[j+3] == 't')goto hoge;
            }
        }
        hoge:
        printf("%s\n",str);
        memset(str,0,sizeof(str));
    }
    return 0;
}

C++: #include <iostream>
#include <vector>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <functional>
#include <string>
#include <algorithm>
#include <string>
#include <climits>
#include <iomanip>
#include <utility>

#define REP(i, n) for (int (i) = 0; (i) < (int)(n); (i)++)
#define REG(i, a, b) for (int (i) = ((int)(a)); (i) < ((int)(b)); i++)
#define ALL(V) (V).begin(), (V).end()
#define PRINT(STR) cout << (STR) << endl
#define DEBUG(X) cerr << X << " (" << __LINE__ << ", " << __func__ << " )" << endl;

typedef long long ll;
using namespace std;

int main() {
	cin.tie(0); //?????±?????????????????????
	ios::sync_with_stdio(false); //printf??¨??±??????????????????
	string str;
	while (getline(cin, str)) {
		for (int i = 0; i <= 26; i++) {
			string newstr = str;
			for (int j = 0; j < str.size(); j++) {
				if ('a' <= newstr[j] && newstr[j] <= 'z') {
					newstr[j] = str[j] + i;
					if (newstr[j] > 'z') {
						newstr[j] -= 'z';
						newstr[j] += 'a';
					}
				}
			}
			//cerr << newstr << endl;
			if (newstr.find("the", 0) != string::npos ||
					newstr.find("this", 0) != string::npos ||
					newstr.find("that", 0) != string::npos) {
				cout << newstr << endl;
				break;
			}
		}
	}
	return 0;
}

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

bool find(string str, string can) {
  string tmp_can = ' ' + can + ' ';
  string tmp_str = ' ' + str + ' ';
  for (int i = 0; i < tmp_str.length(); ++i) {
    if (string::npos != tmp_str.find(tmp_can, i)) {
      return true;
    }
  }
  return false;
}

int main() {
  string str;
  string candies[] = {"this", "the", "that"};
  while(getline(cin, str)) {
  for (int m = 0; m < 25; ++m) {
    for (int i = 0; i < str.length(); ++i) {
      if (str[i] == ' ') {
        continue;
      }
      if (str[i] == ',' || str[i] == '.') {
        str[i] = ' ';
        continue;
      }
      int char_id = static_cast<int>(str[i]) - 97;
      int shifted = static_cast<int>(char_id + 1);
      str[i] = static_cast<char>(shifted % 26 + 97);
    }
    cout << str << endl;
    for (int i = 0; i < sizeof(candies) / sizeof(candies[0]); ++i) {
      if (find(str, candies[i])) {
        cout << "!!!" << endl;
        break;
      }
    }
  }
  }
  return 0;
}

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

#define REP(i,s,e) for(int i=int(s);i<=int(e);i++)
#define rep(i,n) for(int i=0;i<int(n);i++)

#define EPS 1e-6

using namespace std;

bool f(string a){

	string::size_type p=a.find("the");
	string::size_type q=a.find("this");
	string::size_type r=a.find("that");
	if(p!=string::npos || q!=string::npos || r!=string::npos)
	return true;
	else return false;

	}

int main(){

   string s,s1;

   while(getline(cin,s)){


	int n=s.size();

	rep(k,26){
	s1=s;
	rep(i,n){

	if('a'<=s1[i] && s1[i]<='z'-k) s1[i]+=k;
	if(k!=0 && 'z'+1-k<=s1[i] && s1[i]<='z') s1[i]+=k-26;
	}

	if(f(s1)){ cout << s1 << endl; break; }

	}


	}


    return 0;
}

C++: #include <stdio.h>
int check(int a,int b,int c)
{
    //printf("[%d][%d][%d]\n",a,b,c);
    if(a != 14)return 0;
    else if(b == 23)return 1;
    else if(b == 1 && c == 10)return 1;
    else if(b == 19 && c == 19)return 1;
    else return 0;
}

int main()
{
    int longth,mem = 0;
    while(1)
    {
        char str[90] = {0};
        int mem1[90] = {0},mem2[90] = {0};
        if(scanf("%c",&str[0]) == -1)return 0;
        if(str[0] >= 'a' && 'z' >= str[0])mem1[0] = str[0] - 'a' + 1;
        for(int i = 1; i < 80; i++)
        {
            scanf("%c",&str[i]);
            if(str[i] == '\n')break;
            longth = i;
            if(str[i] >= 'a' && 'z' >= str[i])mem1[i] = str[i] - 'a' + 1;
        }
        for(int i = 0; i < longth; i++)
        {
            if(mem1[i] == 0);
            else if(mem1[i + 1] != 0)
            {
                if(mem1[i] <= mem1[i + 1])mem2[i] = mem1[i + 1] - mem1[i];
                else mem2[i] = 26 - mem1[i] + mem1[i + 1];
            }
        }
        /*for(int i = 0; i < longth; i++)
        {
            printf("[%d]",mem2[i]);
        }
        printf("\n");*/
        for(int i = 0; i < longth; i++)
        {
            if(mem2[i] != 0)/*printf("[%d]\n",i);*/if(check(mem2[i],mem2[i + 1],mem2[i + 2]))if(mem1[i] <= 20)mem = 20 - mem1[i];else mem = 26 - mem1[i] + 20;
            //else printf("no\n");
        }
        //printf("{{%d}}\n",mem);
        for(int i = 0; i < longth + 1; i++)
        {
            if(str[i] >= 'a' && 'z' >= str[i])printf("%c",(str[i] - 'a' + mem) % 26 + 'a');
            else printf("%c",str[i]);
        }
        printf("\n");
    }
}

C++: #include<iostream>
using namespace std;
int main(){
  string s;
  while(getline(cin,s)){
    for(int i=0; i<26; i++){
      for(int j=0; j<s.size(); j++){
	if(s[j] == 'z') s[j] = 'a';
	else if(s[j] >= 'a' && s[j] < 'z') s[j]++;
      }
      if(s.find("this") != string::npos ||
	 s.find("the") != string::npos||
	 s.find("that") != string::npos){
	cout <<s<<endl;
	break;
      }
    }
  }
  return 0;
}