Creates symbol table mapping letter grade to numerical score

Question

Problem

Write a client program GPA.java that creates a symbol table mapping letter grades to numerical scores, as in the table below, then reads from standard input a list of letter grades and computes and prints the GPA (the average of the numerical scores of the corresponding grades).

 A+      A        A-      B+     B      B-      C+    C     C-      D       F
4.33  4.00  3.67  3.33  3.00  2.67  2.33  2.00  1.67 1.00  0.00