Here "fstream.h" header file is included for File Handling functions.
In beginning of program main's argument 'argc' is checked to confirm that at shell at least one file name is provided to know the size of. It displays the correct syntax inside the condition where it reaches if wrong syntax is used & the exits the program.
Then it creates an Input Stream object by <ifstream fin;>, then inside the 'for i' loop it opens the files in input mode one by one at each loop iteration.
Inside 'for i' loop the 'while !fin.eof' loop runs for the number of bytes in the file opened in that iteration & store it in 'count' variable.
Then its added to 'totalcount' variable, each file is closed at end of each iteration.
Then at end of 'for i' loop the total size is displayed in bytes & kiloBytes.