Go: package main
import (
	"fmt"
	"os"
	"bufio"
)

var sc = bufio.NewScanner(os.Stdin)

func main(){
	sc.Scan()
	str := sc.Text()
	// rev_str := make([]string, len(str))
	defer fmt.Println()
	for _, v := range []rune(str){
		defer fmt.Print(string(v))
	}
}

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

C++: #include <iostream>
#include <string>
using namespace std;
int main(void){
    int len;
    string a;
    std::cin >> a;
    len =a.length();
    if(len <= 20){
        for(int i = len - 1; i >=0; i--){
            if(isupper( a.at(i) )  != 0) return 0;
        }
        for (int j = len - 1; j >= 0; j--){
            std::cout << a.at(j);
        }
    }
    
    return 0;
}

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

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

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

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

using namespace std;

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

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

int main(){
    string str;
    cin >> str;
    for(auto it=str.rbegin();it!=str.rend();++it)cout << *it;
    return 0;
}

C++: //-------------
//include
//-------------
#include <map>
#include <list>
#include <cmath>
#include <vector>
#include <string>
#include <cctype>
#include <cstdlib>
#include <iostream>
#include <algorithm>
using namespace std;
//-------------
//typedef
//-------------
typedef  long long LL;
typedef  vector<int> VI;
typedef  vector<double> VD;
typedef  string STR;
typedef  pair<int, int> PII;
typedef  vector<int, int> VII;
typedef  map<string, int> MSI;
//-------------
//utillty
//-------------
#define ALL(a)  (a).begin(),(a).end()
#define MK make_pair
#define PB push_back
#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())
#define COUT(a) cout<<a<<endl
#define POW2(a) pow(a, 2.0)
//-------------
//repetition
//-------------
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)
//-------------
//debug
//-------------
#define dump(x)  cerr << #x << " = " << (x) << endl;
#define dumpl(c) REP(i,SZ(c))cerr<<#c<<i<<"="<<(c[i])<<endl;
#define debug(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << endl;

const int MOD = 1000000007;
int main()
{
	STR A;
	cin >> A;
	REP(i,SZ(A))
	{
		cout << A[SZ(A)-1-i];
	}
	cout<<endl;
#ifdef _DEBUG
	while(1);
#endif // _DEBUG

	return 0;
}

C++: #include<iostream>

using namespace std;



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

C++: #include <iostream>
#include <cstdio>
#include <vector>
#include <list>
#include <algorithm>
#include <cmath>
#include <stack>
#include <set>
using namespace std;

#define REP(i,n) for(int (i)=0; (i)<(n); (i)++)
#define FOR(i,a,b) for(int (i)=(a); (i)<(b); (i)++)
#define PUSH(n,v) for(int i=0; i<(n); i++) {int j; cin >> j; v.push_back(j);}
#define ALL(v) v.begin(), v.end()

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

C++: #include <string.h>

#include <iostream>

int main() {
	char str[21];
	std::cin >> str;

	for (int i = strlen(str) - 1; i >= 0; i--)
			std::cout << str[i];

	std::cout << std::endl;
}

C++: #include <iostream>
#include <string>
using namespace std;
int main(void){
    // Your code here!
    string s;
    
    cin >> s;
    
    for(int i=s.length(); i>=0; i--){
        cout << s[i];
    }
    cout << "\n";
}

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

int main(){
  std::string s,t;
  std::cin >> s;
  while(!s.empty()){
    t += s.back();
    s.pop_back();
  }
  std::cout << t << std::endl;
  return 0;
}

C++: #include<stdio.h>

int main(void){
  char str[21],rts[21];

  fgets(str,sizeof(str),stdin);
  sscanf(str,"%20s",str);

  int i=0;
  while(str[i+1]!='\0'){
    i++;
  }
  
  int j=0;
  for(j;j<=i;j++){
    rts[j]=str[i-j];
  }
  
  puts(rts);

  return 0;
}

C++: #include<bits/stdc++.h>
#define rep(i,n) for(int i=0; i<n; i++)
using namespace std;
int main(){
  string s;
  cin >> s;
  for(int i=s.size()-1; i>=0; i--){
    cout << s[i];
  }
  cout << endl;
  return 0;
}

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

int main()
{
	char s[21];
	cin.getline(s, 21, '\n');
	int l = strlen(s);
	for (int i = l - 1; i >= 0; i--)
		cout << s[i];
	return 0;
}

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

int main() {
    std::string str;
    std::cin >> str;

    std::reverse(str.begin(), str.end());
    std::cout << str << std::endl;

    return 0;
}

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

using namespace std;

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

C++: #include <algorithm>
#include <cmath>
#include <climits>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <fstream>
#include <iostream>
#include <list>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>
#include <cassert>
#include <functional>

using namespace std;

#define LOG(...) printf(__VA_ARGS__)
//#define LOG(...)
#define FOR(i,a,b) for(int i=(int)(a);i<(int)(b);++i)
#define REP(i,n) for(int i=0;i<(int)(n);++i)
#define ALL(a) (a).begin(),(a).end()
#define RALL(a) (a).rbegin(),(a).rend()
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define SORT(c) sort((c).begin(),(c).end())
#define RSORT(c) sort((c).rbegin(),(c).rend())
#define CLR(a) memset((a), 0 ,sizeof(a))

typedef long long ll;
typedef unsigned long long ull;
typedef vector<bool> vb;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<vb> vvb;
typedef vector<vi> vvi;
typedef vector<vll> vvll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int dx[] = { -1, 0, 1, 0 }; const int dy[] = { 0, 1, 0, -1 };

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

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<cstdio>
#include<cstring>
using namespace std;
int main(void)
{
    int n;
    char sti[21];
    scanf("%s",sti);
    n=strlen(sti);
    for(int i=n-1;i>=0;i--){
        cout<<sti[i];
    }
    cout<<"\n";
}

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

static void inputString(std::vector<char>& v1)
{
    std::string tmp;

    if (0x00 == &v1) {
        std::cerr << "v1 is null" << std::endl;
        exit (1);
    }

    std::cin >> tmp;
    for (int i = 0; i < tmp.size(); i++) {
        v1.push_back(tmp.at(i));
    }
}

static void reverseString(std::vector<char>& v1, std::vector<char>& v2)
{
    if (0x00 == &v1 || 0x00 == &v2) {
        std::cerr << "v1 or v2 are null." << std::endl;
        exit (1);
    }

    if (v2.empty()) {
        v2.resize(v1.size());
    }

    std::reverse_copy(v1.begin(), v1.end(), v2.begin());
}

int main()
{
    std::vector<char> vec1;
    std::vector<char> vec2;
    
    inputString(vec1);
    reverseString(vec1, vec2);
    for (int i = 0; i < vec2.size(); i++) {
        std::cout << vec2.at(i);
    }
    std::cout << std::endl;

    return 0;
}