Create knapsack.cpp 

Write a C++ program knapsack.cpp which, given n items where the i-th item has value vi and
weight wi
, computes and prints the maximum possible total value of a selected subset of items (out
of the n items) whose total weight equals exactly W (which is another given number), and prints
0 if such subset of items does not exist. Your program should get its input from cin. The input is
a sequence of positive integers in the order of W n v1 w1 v2 w2 . . . vn wn. Example runs of valid
input arguments are (the first line is the command line, the second line is the input and the third
line is the expected output of your program).

Note: Missed few test cases