C :

#include<stdio.h>   

int main(){  
	int x;
	scanf("%d",&x);
	
	int q = x / 1000;
	int b = x / 100 % 10;
	int s = x / 10 % 10;
	int g = x % 10;
	
	int c = g * 1000 + s * 100 + b * 10 + q;
	printf("%d",c);

	return 0; 
} 

C++ :

#include<iostream>
using namespace std;
int main(){
	int i,a,b,c,d;
	cin>>i;
	a=i/1000;
	b=i/100%10;
	c=i/10%10;
	d=i%10;
	cout<<d*1000+c*100+b*10+a;
}

Pascal :

var n,g,s,b,q:longint;
begin
  read(n);
  g:=n mod 10;
  s:=n div 10 mod 10;
  b:=n div 100 mod 10;
  q:=n div 1000;
  writeln(g*1000+s*100+b*10+q);
end.

Java :

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
			Scanner scanner=new Scanner(System.in);
			int m=scanner.nextInt();
			int x=m%10000/1000;
			int a=m%1000/100;
			int b=m%100/10;
			int c=m%10;
			int d=x+a*10+b*100+c*1000;
		System.out.print(d);  
			
	}
}

Python :

a=int(input())
b=a//1000;
c=(a//100)%10;
d=(a//10)%10;
e=a%10;
print(e*1000+d*100+c*10+b)