Go: package main

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

func reverse(s string) string {
	runes := []rune(s)
	for i, j := 0, len(runes)-1; i < j; i, j = i+1, j-1 {
		runes[i], runes[j] = runes[j], runes[i]
	}
	return string(runes)
}

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Scan()
	input := scanner.Text()
	fmt.Println(reverse(input))
}

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

using namespace std;
int main()
{
   char s[21];
   int n;
   cin >> s;
   n = strlen( s );
   for(i=n-1;i<=0;i--)
      cout << s[i];
   cout << endl;
   return 0;
}

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

int main()
{
    char s[21] = {};
    scanf("%20s", s);
    for (int i = strlen(s) - 1; i >= 0; --i) putchar(s[i]);
    puts("");
}

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

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

C++: #include<stdio.h>
#include <string.h>
int main()
{
    char a[30];
    scanf("%s",&a);
    strrev(a);
    printf("%s\n",a);
    return 0;
}

C++: process.stdin.resume();
process.stdin.setEncoding('utf8');

process.stdin.on("data",function(chunk){
    console.log(chunk.split("").reverse().join())
})

C++: #include <iostream>
#include <sstream>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <string>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <numeric>
#include <climits>
#include <cfloat>
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(int argc, char *argv[]) {
  string str;

  cin >> str;
  string::reverse_iterator itr = str.rbegin();
  while (itr != str.rend()) {
    cout << *itr;
    itr++;
  }
  cout << 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>

using namespace std;

class String{
private:
	int length;
public:
	String();
	int str_len(char* str);
};

String::String(){
	length = 0;
}

int String::str_len(char* str){
	int i=0;
	while(str[i++]){
		length++;
	}
	return length;
}

int main(void){

	char str[20];
	int len;
	String string;

	cin >> str;
	len = string.str_len(str);

	for(int i=len-1;i>=0;i--){
		cout << str[i] ;
	}
	return 0;
}

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


char* reverse(char *A){
	char* save = A;
	while (*A) {
		++A;
	}
	char* p = save;
	--A;
	for (; p < A; --A) {
		char t = *A;
		*A = *p;
		*p = t;
		++p;
	}
	return save;
}


int main() {
	char A[100];
	cin >> A;
	cout << reverse(A) << endl;
}

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

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()
{
        string str;
        cin >> str;

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

        return 0;
}

C++: #include<iostream>
#include<iomanip>
#include<string>
#include<algorithm>
#include<functional>
#include<vector>
#include<math.h>
#define L(_i,_N) for(int _i=0;_i<_N;_i++)
#define C(_Dis) cout<<_Dis<<endl;

using namespace std;

typedef long long int lli;

int main() {
	string Str;
	cin >> Str;
	reverse(Str.begin(),Str.end());
	C(Str);
	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
int main() {
    string s;
    cin >> s;
    reverse(s.begin(),s.end());
    cout << s << endl;
}

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

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

C++: #include<stdio.h>
#include<string.h>
#include<iostream>
using namespace std;
int main()
{
    char str[22];
    int i,j;
    cin>>str;
   /* for(i=0;;i++)
    {
        if(str[i]=='\0')
        break;
    }*/
    int l=strlen(str);

    for(j=l-1;j>=0;j--)
    {
        cout<<str[j];
    }
    return 0;
}

C++: #include<bits/stdc++.h>

using namespace std;

main() {
	char str[100];
	int len=0;
	int i;
	scanf("%s",str);

	len=0;
	while(str[len] != '\0') {
	len++;
		}

	for(i=len-1;i>=0;i--) {
	printf("%c",str[i]);
		}
	printf("\n");
	
}

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 << "\0\n";
	return 0;
}

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

int main(){
	char ori[20], rev[20];
	cin >> ori;
	
	int size = 0;

	for(int i = 0; ori[i] != 0; i++){
		size++;
	}

	
	for(int i = 0; i < size; i++){
		rev[i] = ori[size-1-i];
	}
	rev[size] = 0;
	
	cout << rev << endl;
	
	return(0);
}

C++: //
// Created by Undefined on 2018/2/2.
//

#include <iostream>
#include <cstring>

using namespace std;

int main () {
    char s[21], tmp;
    gets(s);
    for (int i = 0, j = strlen(s) - 1; i < j; i++, j--) {
        tmp = s[i];
        s[i] = s[j];
        s[j] = tmp;
    }
    printf("%s\n", s);
}

C++: #include <stdio.h>

int main(){

	char str[20] = {},i;
	
	scanf("%s", str);
	
	for (i = 0; i < 20; i++){
		if (str[19 - i] >0){ printf("%c", str[19-i]); }
	}printf("\n")

	return 0;
}

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

int main()
{
	string inp;

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

C++: #include<iostream>

char str[21];

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

C++: #include <iostream>
#include <cstdio>
#include <vector>
#include <string>
#include <array>
#include <queue>
#include <deque>
#include <set>
#include <list>
#include <map>
#include <stack>
#include <utility>
#include <algorithm>
#include <numeric>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cctype>
#include <cstring>
#include <climits>
#include <bitset>
#include <random>
#include <functional>
#include <sstream>
#include <iomanip>

using namespace std;

#define _CRT_SECURE_NO_WARNINGS
#define rep(i, n) for(int i=0; i<(n); i++)
#define FOR(i, m, n) for(int i=(m);i<(n);i++)
#define SZ(x) ((int)(x).size())
#define all(x) (x).begin(),(x).end()
#define SORT(x) sort((x).begin(),(x).end())
#define REVE(x) reverse((x).begin(),(x).end())
#define mp make_pair
#define pb push_back

typedef vector<int> VI;
typedef vector<string> VS;
typedef vector<vector<int>> VVI;
typedef pair<int, int> PII;
typedef long long LL;

int main() {
	string s;
	cin >> s;
	REVE(s);
	cout << s << endl;
}

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

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

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

using namespace std;

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


	return 0;
}

C++: #include<iostream>
#include<vector>
#define N 20

using namespace std;

int main() {

	vector<char> str(20);

	int i = 0,j;

	while(cin >> str[i]){
		i++;
	}

	for(j = i-1;j >=0;j--){
		cout << str[j];
	}
	cout << endl;
	
	return 0;
}