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 <iostream>
#include <cstdlib>
#include <cstdio>
#include <cmath>
#include <stack>
#include <cctype>
#include <complex>
#include <vector>
#include <algorithm>

using namespace std;


bool solve(){

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

int main(){
	cout.setf(ios::fixed);
	cout.precision(10);
	solve();

	return 0;
}

C++: #include<stdio.h>
#include<string.h>
int main()
{

    char str,rev,arr[100];
    gets(arr);
    strrev(arr);
    printf("%s",arr);
    return 0;

}

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

int main(){
	std::string st;
	std::cin >> st;
	
	while(!(st.empty())){
		std::cout << st.back();
		st.pop_back();
	}
	
	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 <iostream>
#include <string>

using namespace std;

int main()
{
    string FirstString;

    cin >> FirstString;

    int PanjangString = FirstString.length();

    for(int a = PanjangString-1; a >= 0; a--)
    {
        cout << FirstString[a];
    }
    cout << endl;

}

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

int main() {
  char str[30];
  int l;
  char tmp;

  cin >> str;
  l = strlen(str);
  for (int i=0; i<l/2; i++) {
    tmp = str[i];
    str[i] = str[l-i-1];
    str[l-i-1] = tmp;
  }
  cout << str << endl;
  return 0;
}

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

int main()
{
	std::string str;

	std::cin >> str;

	for(int i=str.length()-1;i>=0;--i)
	{
		if(str.length()==0)
			break;

		std::cout << str[i];
	}
	std::cout << '\n';
}

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

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

int main(){
	std::string st;
	
	std::cin >> st;
	
	for(int i = st.size(); i>=0; --i){
		std::cout << st[i];
	}
	
	return 0;
}

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

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

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

long long int gcd(long long int l, long long int r) {
	assert(l > 0 && r > 0);
	if (l > r)return gcd(r, l);
	else {
		const long long int num = r%l;
		if (num) {
			return gcd(l, num);
		}
		else {
			return l;
		}
	}
}
long long int lca(long long int l, long long int r) {
	return l / gcd(l, r)*r;
}
int main() {
	string st; cin >> st;
	reverse(st.begin(), st.end());
	cout << st << endl;
	return 0;
}

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

int main(void)
{
  char str[21], reversed_str[21];
  scanf("%s", str);
  int len = strlen(str);

  int i;
  for(i=0; i<len; ++i){
    reversed_str[i] = str[len-1-i];
  }
  reversed_str[len] = '\0';

  printf("%s\n", reversed_str);

  return 0;
}

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

int main(){
	char str[64];
	int i;
	cin >> str;
	for(i=1;i<=strlen(str);i++){
		cout << str[strlen(str)-i];
	}
	cout << endl;
	return 0;
}

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

using namespace std;

int main() {

	char str[20];

	cin >> str;

	//cout << strlen(str) << endl;

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

	return 0;

}

C++: #include<iostream>
#include<cstdio>
#include<utility>
#include<climits>
#include<cmath>
using namespace std;

int main()
{
	int i, j;

	char str[20] = {};
	for (i = 0; cin >> str[i]; i++)
	{}

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

C++: #include <stdio.h>
#include <string.h>
int main()
{
    char a[50];

    int i,j,b;
        scanf("%s",&a);
        b=strlen(a);
        for(i=b;i>=0;i--)
        {
        printf("%c",a[i]);
        }
    return 0;
}

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

int main() {
	string a,b;
	int i, l;
	
	cin >>a;
	l=a.size();
	b="";
	for (i=0;i<l;i++){
		b=a.substr(i,1)+b;
	}
	cout << b<<endl;
	return 0;
}

C++: #include<stdio.h>
#include<stdlib.h>
#include<iostream>
#include<string>
#include<algorithm>
#include<vector> 
#include<limits>
#include<numeric>
#include<math.h>
using namespace std;

#define rep(i, n) for(int i = 0; i < (int)(n); i++)
#define in(x) cin >> x
#define out(str) cout << str << endl

template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }

string S;

int main(){
    cin>>S;
    reverse(S.begin(),S.end());
    out(S);
}

C++: #include<stdio.h>
#include<string.h>
int main(){
    int l;
    char s[32],r[32];
    scanf("%s",s);
    l=strlen(s);
    for(int i=0;i<l;i++){
        r[l-i-1]=s[i];
    }
    for(int i=0;i<l;i++){
        printf("%c",r[i]);
    }
    printf("\n");
    return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <string>
using namespace std;
int main() {
	string str;
	cin>>str;
	reverse(str.begin(),str.end());
	cout<<str<<endl;
}

C++: #include<string>
#include<algorithm>
#include<iostream>
int main(){using namespace std;string s;getline(cin,s);reverse(s.begin(),s.end());cout<<s<<endl;}

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


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

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

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

using namespace std;



int main(){
	string str;
	int i;
	
	cin >> str;

	i = str.size()-1;

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

}

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

long long int gcd(long long int l, long long int r) {
	assert(l > 0 && r > 0);
	if (l > r)return gcd(r, l);
	else {
		const long long int num = r%l;
		if (num) {
			return gcd(l, num);
		}
		else {
			return l;
		}
	}
}
long long int lca(long long int l, long long int r) {
	return l / gcd(l, r)*r;
}
int main() {
	string st; cin >> st;
	reverse(st.begin(), st.end());
	return 0;
}

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

using namespace std;

void swap(char *a, char *b){
  char tmp = *a;
  *a = *b;
  *b = tmp;
}

int main()
{
  char str[32];
  scanf("%s", str);
  int len = strlen(str);
  for(int i=0;i<len/2;i++)
    swap(&str[i], &str[len-i-1]);

  puts(str);
  return 0;
}

C++: #include<bits/stdc++.h>
int main()
{
	int i=21;
	char st[21];
	memset(st,false,sizeof(st));
	scanf("%s",&st);
	for(;i--;){
		if(st[i]){
			if(isalnum(st[i]) || isalpha(st[i])){
				printf("%c",st[i]);
			}	
	}
}}

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

int main(void){
	string str;
	cin >> str;
	for(int i=static_cast<int>(str.size())-1;i>=0;i--)
		cout << str.at(i);
	cout << endl;
}