How to defining diagram and algorithm

Question

A text file of hundreds of students' results might include data such as first name, second name, student ID, and number grade. For example five records of such a file might look like this:

10546 Jones  Sally 56
09834 Zula  Marcos 72
10236 Winston  Alexander 81
11643 Granger  Thomas 45
10894 Lobos Alexia 75

Develop an algorithm to read such a file of results. It must count the total number of students and count how many students belong to the letter grade groups given in the example below. Ensure your algorithm uses a CASE statement to correctly classify and tally. For example, based on the above excerpt from the file, the output of the algorithm would be:


Total number of students receiving a high distinction (HD): 1
Total number of students receiving a distinction (D): 2
Total number of students receiving a credit (C): 0
Total number of students receiving a pass (P): 1
Total number of students receiving a fail (F): 1
Total number of students: 5

**Hint - HD: 80+, D: 70-79, C: 60-69, P: 50-59, F: <50**

Submit:
a. defining diagram and
b. algorithm for this question.