create an AWK program that takes a CSV (comma separated variable) file named on the command line and outputs a histogram of the grades in the file. The first five fields of the input will look like: "lastname","firstname","id","section","grade"...

The output should be a series of lines like

100

99 **

98 ***

97

96 *

which indicate that there were 0 100s, 2 99s, 3 98s, 0 97s, and 1 96 in the input file.