C :

#include<stdio.h>
int main()
{
	int a,b,c,d;
	scanf("%d",&a);
	b=a/10;
	c=a%10;
	if(c==0) d=b;
	else d=c*10+b;
	printf("%d",d);
	return 0;
}

C++ :

#include<bits/stdc++.h>
using namespace std;
int main(){
	int a,b,c;
	cin>>a;
	b=a/10;
	c=a%10*10;
	cout<<b+c<<endl;
    return 0;
}

Java :

import java.util.Scanner;

public class Main {
	 
    /**
     * @param args
     */
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int g = a%10;
		int s = a/10;
		int sum = g*10+s;
		System.out.println(sum);
		
	}
	public static void printArr(int [] a){
		for (int i = 0 ;i<= a.length - 1 ;i++) {
			System.out.print( a[i] + " ");
		}
	}
}

Python :

#!/usr/bin/python3
a=int(input())
s=a//10
m=a%10
print(s+m*10)