Question

Using C programming

For this project, you have been tasked to read a text file with student grades and perform several operations with them. First, you must read the file, loading the student records. Each record (line) contains the student’s identification number and then four of the student’s numerical test grades. Your application should find the average of the four grades and insert them into the same array as the id number and four grades. I suggest using a 5th array position to hold the computed average. Once the file has been read and the averages calculated and stored in the array, you must sort the list by grade in descending order. Finally, the records should be printed to screen in descending final grade order with statistics at the end of the file for the class average, highest and lowest grades. We will cover the aspects you need to complete this project over the next 3-4 weeks. Objectives: • Use of the FILE* and file functions. • Use of functions to include the passing of arrays and or array elements. • Implementation of a common (bubble sort) sorting algorithm. • Display formatted output using input/output statements. • Use format control strings to format text output. • Use C data types. Requirements: Your program should make use of the following functions.

1. A function to read the file into an array of arrays. This function should take an empty multi-dimensional array from the caller. The function should ask the user for the name of the file. You may assume the file name entered will be accurate and accessible. You may omit this requirement and hard code the path to the file. You will be given a test file (shown below). I suggest hard coding the filename while you develop your project to save typing it over and over while you test.

2. A function to compute the grade for each array/record. This function should access the array and average the test grades, inserting the final average into the last position for each record as a float.

3. A function to sort the array of arrays by final grade in descending order (highest grade first). This function should take the entire array.

4. A function to print out the results of the operation to screen calculating the required totals and formatting the output appropriately. This function should take the entire array as well. Your program is expected to only deal with fractional values. Therefore, you are required to use a multi-dimensional array of type float or double. Your program will not have to resize your array; you may hard code the size of the array using a constant (#define). The test files will have 10 records/students, a student number followed by 4 grades. You may not use any global variables save for the use of a constant for array size if you wish as shown often in some examples

grades input file

6814 85 86 92 88

7234 76 81 84 78

6465 87 54 68 72

7899 92 90 88 86

9901 45 78 79 80

8234 77 87 84 98

7934 76 91 84 65

7284 56 81 87 98

7654 76 87 84 88

3534 86 81 84 73

Answer 1

Code:

#include<stdio.h>
#include<malloc.h>

#define MAX_ROWS 10//Number of records in file

//Function prototypes
void inputGrades(float *arr[MAX_ROWS]);
void calculateAverage(float *arr[MAX_ROWS]);
void sortArray(float *arr[MAX_ROWS]);
void display(float *arr[MAX_ROWS]);


int main()
{
    float *arr[MAX_ROWS];//Declaring array of pointers and will be used as a 2D array
    for(int i = 0; i < MAX_ROWS; i++)
    //Allocating memory to 2D array
    arr[i] = (float *)malloc(sizeof(float)*6);
    inputGrades(arr);//Input grades from file
    calculateAverage(arr);//Calculate average for each array
    sortArray(arr);//Sort array by grades in descending order
    display(arr);//Dsiplay resultant array
    return 0;
}

//This function takes input a file name from the user which contains
//grades of student in unsorted order and read grades from the file in array
void inputGrades(float *arr[MAX_ROWS])
{
    char fileName[20];
    printf("Enter file name: ");
    scanf("%s", fileName);//Input file name
    FILE *f = fopen(fileName, "r");//Open file
    if(f == NULL)
    {
        printf("Cannot open file");
        exit(0);
    }
    int i = 0;
    while(fscanf(f, "%f %f %f %f %f", &arr[i][0], &arr[i][1], &arr[i][2], &arr[i][3], &arr[i][4]) == 5)//Reading student ID and grades from file
        i++;
}

//Function to calculate average of each grades for a student and store it in last position of array
void calculateAverage(float *arr[MAX_ROWS])
{
    for(int i = 0; i < MAX_ROWS; i++)
        arr[i][5] = (arr[i][1] + arr[i][2] + arr[i][3] + arr[i][4])/4;//Calculate average of grades and store in 5th position
}

//Function to display the result after sorting
void display(float *arr[MAX_ROWS])
{
    float totalAvg = 0;
    printf("\n%11s%11s%11s%11s%11s%11s", "Student ID", "Test 1", "Test 2", "Test 3", "Test 4", "Final");
    printf("\n\n******************************************************************");
    for(int i = 0; i < MAX_ROWS; i++)
    {
        printf("\n%11.0f %10.0f %10.0f %10.0f %10.0f %10.2f", arr[i][0], arr[i][1], arr[i][2], arr[i][3], arr[i][4], arr[i][5]);
        totalAvg += arr[i][5];//Adding average for each student
    }
    printf("\n******************************************************************");
    totalAvg = totalAvg/MAX_ROWS;//Class average
    printf("\nClass Average: %.2f\tHighest Grade: %.2f\t Lowest Grade: %.2f", totalAvg, arr[0][5], arr[9][5]);
}

//Function to implement bubble sort and sort the array by average grades
//in descending order
void sortArray(float *arr[MAX_ROWS])
{
    int i, j;
    for (i = 0; i < MAX_ROWS - 1; i++)
        for (j = 0; j < MAX_ROWS - i - 1; j++)
            if(arr[j][5] < arr[j+1][5])
            {
                //Swap row a[j] and row a[j+1]
                float *temp = arr[j];
                arr[j] = arr[j+1];
                arr[j+1] = temp;
            }
}

Output: