C :

#include <stdio.h>
void main()
{
	int n;
	scanf("%d",&n);
	if(n%2==0){
		printf("%d\n",2);
	}
	if(n%3==0){
		printf("%d\n",3);
	}
	if(n%5==0){
		printf("%d\n",5);
	}
	if(n%7==0){
		printf("%d\n",7);
	}
	  
}

C++ :

#include <iostream>
using namespace std;
 
int main(){
	int n;
	cin>>n;
	if(n % 2 == 0){
		cout<<2<<endl;
	}
	
	if(n % 3 == 0){
		cout<<3<<endl;
	}
	
	if(n % 5 == 0){
		cout<<5<<endl;
	}
	
	if(n % 7 == 0){
		cout<<7<<endl;
	}
}

Pascal :

var a:longint;
begin
read(a);
if a mod 2=0 then writeln('2');
if a mod 3=0 then writeln('3');
if a mod 5=0 then writeln('5');
if a mod 7=0 then writeln('7');
end.

Java :

import java.util.Scanner;
public class Main {
		public static void main(String[] args) {
			Scanner sc = new Scanner(System.in);
			int n = sc.nextInt();
			if(n % 2 == 0){
				System.out.println(2);
			}if(n % 3 == 0){
				System.out.println(3);
			}if(n % 5 == 0){
				System.out.println(5);
			}if(n % 7 == 0){
				System.out.println(7);
			}
		}
}

Python :

n = int(input())  
if n % 2 == 0:
    print(2)
if n % 3 == 0:
    print(3)
if n % 5 == 0:
    print(5)
if n % 7 == 0:
    print(7)