x=148;i;j;char*p,q[];main(t){for(;gets(p=q+400);)for(t='v\xa4'>>i++&2,p+=strlen(p+--t);*p;p-=t)for(q[j=x-=(i&1?:20)*t]=*p;j%20>q[--j];)q[j]=32;for(p=q;*p;p+=20)puts(p);}
Note that non-ascii characters in the above source code will be escaped (such as \x9f).