SimpleMap and SimpleWriteMap
- Trivial adaptors, but they are useful in some case

Some combined maps will be reference map if the first
template parameter map is reference map or not. If I want
to give a refernce map as first map but there is a non
reference map parameter then I should wrap my first map
to a regular read-write map.

 #!/bin/bash

 for((i=1;i<50;i++))

 do

     echo -n $i ''

     edge_lookup 100 $i

 done