Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

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

func main() {
	scanner.Split(bufio.ScanWords)

	str := nextString()
	for i := len(str) - 1; i >= 0; i-- {
		fmt.Print(str[i:(i + 1)])
	}
	fmt.Print("\n")
}

C++: //include
//------------------------------------------
#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>

using namespace std;

//conversion
//------------------------------------------
inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}

//math
//-------------------------------------------
template<class T> inline T sqr(T x) {return x*x;}

//typedef
//------------------------------------------
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef long long LL;
typedef unsigned long long ULL;

//container util
//------------------------------------------
#define ALL(a)  (a).begin(),(a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define EACH(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i)
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define SORT(c) sort((c).begin(),(c).end())

//repetition
//------------------------------------------
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)

//constant
//--------------------------------------------
const double EPS = 1e-10;
const double PI  = acos(-1.0);

//clear memory
#define CLR(a) memset((a), 0 ,sizeof(a))

//debug
#define dump(x)  cerr << #x << " = " << (x) << endl;
#define debug(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << endl;

int main() {
  string str;

  cin << str;

  for(int i = str.size()-1; i >= 0; i++) cout << str[i];
  cout << endl;
}

C++: #include<iostream>
#include<string>
using namespace std;
int main() {
    string str;
        int i;
        cin >> str;
        for (i = str.length() - 1; i >= 0; i--) {
        cout << str[i];
    }
    cout << endl;
    return 0;
}

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

using namespace std;

int main()
{
	char str[20];
	int length;
	
	cin >> str;
	for(length = 0; str[length] != '\0'; length++);
	
	for(int i = length-1; i > -1; i--){
		printf("%c",str[i]);
	}
	cout << endl;
}

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

int main(){
    string str = "";
    cin >> str;
    for(int i = 0; i < str.size(); i++){
        cout << str[str.size() - i -1];
    }
    return 0;
}

C++: #include<iostream>
#include<stdio.h>
#include<algorithm>
#include<string.h>
using namespace std;

int main(){
  string str;
  cin >> str;
  int l = strlen(str);
  for(int i = l - 1; i >= 0; i--){
    cout << str[i];
  }
  cout << endl;
}

C++: #include<stdio.h>
#include<string.h>
char a[21];
int main()
{
	while (gets(a))
	{
		for (int i = strlen(a) - 1; i >= 0; i--)
			printf("%c", a[i]);
		printf("\n");
	}
	
	return 0;

}

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

using namespace std;

int main (){
	string str;
	cin >> str;
	for(int i = str.size()-1; i >= 0; i++) cout << str[i];
	cout << endl;
	return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <cstdlib>
#include <time.h>
#include <math.h>
#include <vector>
#include <queue>
#include <map>
#include <set>
#include <algorithm>
#include <iterator>
#include <sstream>
#include <string>
#include <bitset>
using namespace std;
#define FOR(I,F,N) for(int I = F; I < (int)(N); I++)
#define rep(i, n) FOR(i, 0, n)
#define FIN(V) cout<<V<<endl
#define pb push_back
#define INF (1 << 30)
typedef pair<int, int> P;
typedef long long ll;
typedef priority_queue<int> pq;
int StrToInt(string);
string IntToStr(int);
int dx[4] = {1, -1, 0, 0};
int dy[4] = {0, 0, 1, -1};

int main(void){
	string S;
	cin >> S;
	for(int i = S.size(); i >= 0; i--)cout << S[i];
	cout << endl;

	return 0;
}

C++: #include<stdio.h>
#include<memory.h>

int main()
{
	char str[30];
	memset(str,0,sizeof(str));
	scanf("%s",&str);
	for(int i=19;i>=0;i--)
		if(str[i])  printf("%c",str[i]);

	return 0;
}

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

using namespace std;

int main(){

  string s;

  cin >> s;

  for( int i = s.size() ; i--;){
    cout << s[i];
  }
  cout << endl;
}

C++: #include <stdio.h>
#include <string.h>

int main(void)
{
	char str[21];
	char rev[21];
	int len;
	int i;
	
	scanf("%s", str);
	
	len = strlen(str) - 1;
	
	for (i = 0; i <= len; i++){
		rev[i] = str[len - i];
	}
	rev[i] = '\0';
	
	printf("%s\n", rev);
	
	return (0);
}

C++: #include <bits/stdc++.h>
#include <string>
using namespace std;
int main()
{
	string a="";

	getline(cin,a);
	reverse(a.begin(), a.end());
	cout<<a<<endl;

	return 0;
}

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

int main(){
  char str;
  cin >> str;
  int l = strlen(str);
  for(int i = l - 1; i >= 0; i--){
    cout << str[i];
  }
  cout << endl;

  return 0;
}

C++: #include <stdio.h>
int main(){
	char str[20];
	int d_len,i;
	d_len=0;
	scanf("%s",&str);
	while(str[d_len]!='\0'){
		d_len++;
	}
	for(i=d_len-1;i>-1;i--)printf("%c",str[i]);
	return 0;
}

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

int main(){
  string s;
  cin >> s;
  int k;
  for(k=s.size();k>=0;k--){
    printf("%c",s[k]);
  }printf("\n");
  return 0;
}

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

using namespace std;

int main(){
	
	string str;
	cin>>str;
	
	reverse(str.begin(),str.end());
	
	cout<<str<<endl;
	
	
}

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

string reverse(string s){
  int n = s.size();
  string r;

  for(int i = n - 1; i >= 0; i--)r += s[i];
  
  return r;
}

int main(){
  string s;
  cin >> s;

  cout << reverse(s) << endl;

  return 0;
}

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

int main() {
  string S;
  cin >> S;
  reverse(S.begin(), S.end());
  cout << S << endl;
}

C++: #include<stdio.h>
#include<stdlib.h>
int main(void){
  char a,b,i,j;
  char rarara[25];
  char papapa[25]; 
  fgets(rarara,sizeof(rarara),stdin);
 for(i=0;rarara[i]!=NULL;i++){};
 a=i;
  for(i=0;i<a;i++)
    papapa[i]=rarara[a-i-1];
  papapa[a]=NULL;
  printf("%s",papapa);
  return 0;
}

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

int main() {
	// your code goes here
	string s;
	cin >> s;
	for(int i=0;i<s.size();i++)
	cout << s[s.size()-i-1];
	cout << endl;
	return 0;
}

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

int main(){

   string str;

   cin>>str;

   reverse(str.begin(),str.end());

   cout<<str<<endl;

   return 0;

}

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

int main() {
	char str[21];
	cin >> str;
	int length = std::strlen(str);
	int x;
	for (int i = 0; i < length; i++){
		x = length - i - 1;
		cout <<str[x];
	}
	cout << "\n";
	return 0;
}

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

using namespace std;

int main( void )
{
  string in;
  while( cin >> in )
  {
     reverse(in.begin(), in.end())
     cout << in << endl;
  }
  return 0;
}

C++: #include <iostream>
#include <cstring>
 
using namespace std;
int main()
{
   char s[21];
   int n,i;
   cin >> s;
   n = strlen( s );
   for(i=n-1;i<=0;i--)
      cout << s[i];
   cout << endl;
   return 0;
}