make a map in dart language and then add another key value ar run time and the  print the whole map

Use Java pl DataFileWords.txt: lovegentlensslovepeacelovekindnesslovepeaceunderstandingkindnessjoypeaceunderstandingfriendshipgentlenssgoodnesslovepeacegoodnesslovegentlensscontrolunderstandingunderstandinggentlensslovepeacepatiencecontrolkindnessgentlensslovepeacejoygoodnesspeacefriendshipgoodnesskindnesslovepeacegoodnesscontrolpatiencejoygentlensspatiencegentlensspatiencekindnessgoodnessjoygentlenssgentlenss

Write a program in C++ which allows the user to input 3 sets (A,B,C) and to display the cartesian product AxBxC of the 3 sets, and then calculate the number of elements in AxBxC. Keep in mind, if the the input looks like A={a,b,c}, B={1,2,3,4}, C={A,B,C,D,E}, the output should look like “AxBxC = {(a,1,A), … ,(c,4,E)} and it has 60 elements”

Could I get an example of a program writen in C that uses qsort() to sort its command line vector argv by the length of the strings? This is part of my first project and I don't understand pointers very well. If you have a video on how it is done that would work too. I looked at the meterial provided to me and I still cant rap my head around it. If this is to big of a question if you could baby step me through how pointers work that would be a great help. Thank you