c++

1. Write a function named "readScores" that reads in a (-1)-terminated list of scores from the user. It will return the corresponding counts of 'A', 'B', 'C', 'D', 'F' and invalid grades (negative scores other than-1 are invalid) based on the standard score system: >=90 A >= 80 B >= 70 C >=60 D >= 0 and