> #include<iostream.h>
> #include<fstream.h>//
> 
> void main()
> {
> 	fstream fin("in.txt",ios::in||ios::out);//
> 	fstream fout("out.txt",ios::out);//
> 	unsigned long input,population,m,dis,m1,t,tt;//;	
> 	while(1)
> 	{
> //		fin>>input;
> 		cin>>input;
> 
> 
> 		if(input==0)
> 			return;
> 
> 		
> 		m=input+1;//initialize m
> 
> 		while(1)
> 		{
> 			population=2*input;//the number of people
> 			dis=0;
> 	
> 			while(1)
> 			{
> 				m1=m-dis;
> 
> 				m1%=population;
> 
> 				if(m1>input||m1==0)
> 				{
> 					dis=population-m1;
> 					if(m1==0)
> 						dis=0;
> 					
> 					population--;
> 
> 				}
> 				else
> 					break;
> 				if(population==input)
> 					break;
> 			}
> 			if(population==input)
> 				break;
> 		 
> 			m++;//selfadding
> //
> 
> //			m+=(input+1);
> /*
> 			t=m/population;
> 			tt=m%population;
> 			if(tt<=input&&tt>0)
> 				m=t*population+input+1;		
> 				*/
> 		}
> 		cout<<m<<endl;	
> 	}
> 
> }