/*
 * Prog_Practice_W5.c
 *
 *  Created on: Jan 14, 2022
 *      Author: johnsontimoj
 */
////////////////////////////////////
//
// Program to calculate the letter grade of a student
// based on 3 scores
//
// inputs: student ID, 3 scores
// outputs: printed letter grade
////////////////////////////////////
#include <stdio.h>

// function declarations (prototypes)
int get_score(int std_num, int cnt);
float calc_ave(int s1, int s2, int s3);
void print_grade(int std_num, float score);
char calc_grade(float score);

int main(void){
	setbuf(stdout, NULL);	// fix code composer issue

	// splash
	printf("\nWelcome to Dr. Johnson's Letter Grade calculation program\n");

	// local variables
	int student_ID;
	int score_1;
	int score_2;
	int score_3;
	float average;

	while(1){
		// get student ID
		printf("\nPlease enter the students ID number:");
		scanf("%i", &student_ID);

		// get scores
		score_1 = get_score(student_ID, 1);
		score_2 = get_score(student_ID, 2);
		score_3 = get_score(student_ID, 3);

		// calculate average
		average = calc_ave(score_1, score_2, score_3);

		// print the letter grade
		print_grade(student_ID, average);

	}// end while
	return 0;
}// end main

int get_score(int std_num, int cnt){
	// function to get a single score for a student
	int score;
	printf("Please enter score # %i for student # %i: ", cnt, std_num);
	scanf("%i", &score);

	return score;
}// end get_score

float calc_ave(int s1, int s2, int s3){
	// function to calculate the normal average of 3 numbers
	return (s1 + s2 + s3)/3.0 ;	// forcing float division
}// end calc_score

void print_grade(int std_num, float score){
	// function to print grades
	// based on scores
	// uses calc_grade()
	char grade;

	// calc grade
	grade = calc_grade(score);

	// print the grade
	printf("Student # %i has a grade of: %c \n", std_num, grade);

	return;
}// end print_grade

char calc_grade(float score){
	// function to calculate the letter grade
	// based on a numeric value
	// using standard grade mapping
	char grade;

	// calculate grade
	if(score >= 90)
		grade = 'A';
	else if(score >= 80)
		grade = 'B';
	else if(score >= 70)
		grade = 'C';
	else if(score >= 60)
		grade = 'D';
	else
		grade = 'F';

	return grade;
}// end calc_grade