using System;

public class Program

{

    public static void Main()

    {

        string a = "Move spaces to the beginning";

        int n = a.Length-1;

        int count =n;

        for(int i=n;i>=0;i--)

    {

        if(a[i] != ' ')

        a[count--] = a[i];

    }

​

    }

}