Command Line Format:
./<productname> <filename> <cityname1> <cityname2>
(where the filename ends with ".txt", and each argument separated by a single comma).
Example:
./Connected cities.txt Boston Pittsburgh
./<productname>
The name of the target file while compiling C++ programs (Connected.cpp) with g++.
<filename>
The name of the input file.
<cityname1>
The name of start city.
<cityname2>
The name of end city.