C :

#include<stdio.h>
int main()
{
    int str[1024] = {0},counter = 0,i = 0, n = 0,k = 0;
    char ch = 'a';
    scanf("%d",&n);
    scanf("%c",&ch);
    for(i = 0;i < n;i++)
    {
        str[i] = 1;
    }
    i = 0;
    k = n;
    while(n > 1)
    {
        if(i >= k)
        {
            i = i%k;
        }    
        if(str[i] == 1)
        {
            counter++;
        }
        if(counter == 3)
        {
            str[i] = 0;
            n--;
            counter = 0;
        }
        i++;
    }
    for(i = 0;i < k;i++)
    {
        if(str[i] == 1)
        {
            n = i + 1;
        }
    }
    printf("%d\n",n);
    return 0;      
}

C++ :

#include <stdio.h> 

const int M = 3; 

int main() 
{ 
    int n, s = 0; 
    scanf("%d", &n); 
    for (int i = 2; i <= n; ++i) 
        s = (s+M)%i; 
    printf("%d\n", s+1); 
    return 0; 
}

Java :

import java.util.Scanner;

public class Main {

	/**
	 * @param args   1947
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner in = new Scanner(System.in);
		
		int j = 0,k = 0,count = 0;
		int n = in.nextInt();
		int[] a = new int[1024];
		for(int i = 0; i < n; i ++){
			a[i] = i+1;
		}
		while(j < 3){
			if(a[k] != 0){
				j ++;
			}
			if(j == 3){
				a[k] = 0;
				j = 0;
				count ++;
			}
			if(count == n-1){
				break;
			}
			k ++;
			if(k == n){
				k = 0;
			}
		}
		for(int i = 0; i < n; i ++){
			if(a[i] != 0){
				System.out.println(a[i]);
				break;
			}
		}
		in.close();
	}

}

Python :

n = input()
n1 = n
a = [1]*n
c = 2
while 1:
    if a[c%n] == 0:
        c +=1
        while a[c%n] == 0:
            c+=1
    a[c%n]=0
    while a[c%n] == 0:
            c+=1
#    print a
    n1-=1
    if n1 == 1:
        break
    c+=1
    while a[c%n] == 0:
            c+=1
    c+=1
    while a[c%n] == 0:
            c+=1
c=1
for i in a:
    if i == 1:
        break
    c+=1
print c