Question

This program is a modification of your program for A3a. Instead of accepting input from user through standard input, you will be taking input from a file. You must take the input file name on the command line Be sure to have simple error checking to be sure the file exists and was successfully opened The input file will have the following format: First 1ine: Number of students Second Line: Number of assignments Third Line: Student Names, space delimited Fourth+ Line(s): Grades for all students for one assignment, space delimited Example of input file format: 2 Joel Sophie 100 97 78 92 62 70 Requirements: - Your program must read input from a file in the proper format, NOT stdin - Your program should accept the filename from the commandline as shown in the example below Your program should be able to handle a file of any reasonable size. (I will not use excessively long student names, but there may be MANY students and grades.) Do not just make your arrays really large, you need to dynamically allocate them Example: $ ./a.out infile.txt Joel 100 Sophie 97 92 70

Here is the (A3b-smallgrades.txt) text file:

Here is the (A3b-largegrades.txt) text file:

Here is the Program A3a without modification:

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <time.h>

void getGrades(int ROWS, int COLS, int grades[ROWS][COLS], char students[COLS][20]);

void printGrades(int ROWS, int COLS, int grades[ROWS][COLS]);

void getStudents(int COLS, char students[COLS][20]);

void printStudents(int COLS, char students[COLS][20]);

void calcGrades(int ROWS, int COLS, int grades[ROWS][COLS], char Fgrades[]);

void printFinalGrades(int COLS, char Fgrades[]);

int main()

{

   srand(time(0));

   int stu = 0, assign = 0;

   char input[50];

   printf("How many students? ");

   fgets(input, sizeof(input), stdin);

   sscanf(input, "%d", &stu);

   printf("How many assignments? ");

   fgets(input, sizeof(input), stdin);

   sscanf(input, "%d", &assign);

   char students[stu][20];

   int grades[assign][stu];

   char final_grade[stu];

   getStudents(stu, students);

   getGrades(assign, stu, grades, students);

   calcGrades(assign, stu, grades, final_grade);

   printf("\n");

   printStudents(stu, students);

   printGrades(assign, stu, grades);

   printFinalGrades(stu, final_grade);

   return 0;

}

void printFinalGrades(int COLS, char Fgrades[])

{

   int i = 0;

   for (i = 0; i < COLS; ++i)

   {

       printf("%10c", Fgrades[i]);

   }

   printf("\n");

}

void calcGrades(int ROWS, int COLS, int grades[ROWS][COLS], char Fgrades[])

{

   int avg = 0;

   int sum = 0;

   int i = 0, j = 0;

   for (i = 0; i < COLS; ++i)

   {

       // Find the sum

       sum = 0;

       for (j = 0; j < ROWS; ++j)

       {

           sum += grades[j][i];

       }

       avg = sum / ROWS;

       if (avg >= 90)

           Fgrades[i] = 'A';

       else if (avg >= 80)

           Fgrades[i] = 'B';

       else if (avg >= 70)

           Fgrades[i] = 'C';

       else if (avg >= 60)

           Fgrades[i] = 'D';

       else

           Fgrades[i] = 'F';

   }

}

void printStudents(int COLS, char students[COLS][20])

{

   int i = 0;

   int numA = COLS;

   for (i = 0; i < numA; ++i)

   {

       printf("%10s", students[i]);

   }

   printf("\n");

}

void getStudents(int COLS, char students[COLS][20])

{

   int i = 0, len = 0;

   for (i = 0; i < COLS; ++i)

   {

       printf("Enter name for Student %d: ", i);

       fgets(students[i], sizeof(students[i]), stdin);

       len = strlen(students[i]);

       students[i][len-1] = '\0';

   }

}

void printGrades(int ROWS, int COLS, int grades[ROWS][COLS])

{

   int i = 0, j = 0;

   for (i = 0; i < ROWS; ++i)

   {

       for (j = 0; j < COLS; ++j)

       {

           printf("%10d", grades[i][j]);

       }

       printf("\n");

   }

}

void getGrades(int ROWS, int COLS, int grades[ROWS][COLS], char students[COLS][20])

{

   int i = 0, j = 0;

   for (i = 0; i < ROWS; ++i)

       for (j = 0; j < COLS; ++j)

           {

               printf("Enter grade for Assignments %d for %s: ", i, students[j]);

               scanf("%d", &grades[i][j]);

           }

}

Answer 1

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
// Prototype declaration of functions
void getGrades(int ROWS, int COLS, int grades[ROWS][COLS], char students[COLS][20]);
void printGrades(int ROWS, int COLS, int grades[ROWS][COLS]);
void getStudents(int COLS, char students[COLS][20]);
void printStudents(int COLS, char students[COLS][20]);
void calcGrades(int ROWS, int COLS, int grades[ROWS][COLS], char Fgrades[]);
void printFinalGrades(int COLS, char Fgrades[]);
// File pointer
FILE *fptr;
// main function definition
int main(int argc, char** argv)
{
// To store number of students and number of assignments
int stu = 0, assign = 0;
// Opens the file in read mode
// command line argument argv[1] contains the file name
fptr = fopen(argv[1], "r");
// Checks if the file pointer is NULL then display the error message and stop
if (fptr == NULL)
{
printf("Cannot open file %s\n", argv[1]);
exit(0);
}// End of if condition
// Reads number of students and number of assignments from file
fscanf(fptr, "%d%d", &stu, &assign);
printf("\n Number of Students %d \n Number of Assignment = %d", stu, assign);
// Matrix for student names
char students[stu][20];
// Matrix for assignment marks
int grades[assign][stu];
// Array for grade
char final_grade[stu];
// Calls the functions to read data from file and calculate grade
getStudents(stu, students);
getGrades(assign, stu, grades, students);
calcGrades(assign, stu, grades, final_grade);
printf("\n");
// Calls the function to display data
printStudents(stu, students);
printGrades(assign, stu, grades);
printFinalGrades(stu, final_grade);

return 0;
}// End of main function

// Function to display final grade of all the students
void printFinalGrades(int COLS, char Fgrades[])
{
int i = 0;
// Loops till number of students
for (i = 0; i < COLS; ++i)
{
// Displays grade
printf("%10c", Fgrades[i]);
}// End of for loop
printf("\n");
}// End of function
// Function to calculate grade
void calcGrades(int ROWS, int COLS, int grades[ROWS][COLS], char Fgrades[])
{
// Initializes the variables
int avg = 0;
int sum = 0;
int i = 0, j = 0;
// Loops till number of cols
for (i = 0; i < COLS; ++i)
{
sum = 0;
// Loops till number of rows
for (j = 0; j < ROWS; ++j)
{
// Calculate total
sum += grades[j][i];
}// End of for loop
// Calculate average
avg = sum / ROWS;
// Checks if average is greater than or equals to 90
if (avg >= 90)
// Assign grade as 'A'
Fgrades[i] = 'A';
// Otherwise checks if average is greater than or equals to 80
else if (avg >= 80)
// Assign grade as 'B'
Fgrades[i] = 'B';
// Otherwise checks if average is greater than or equals to 70
else if (avg >= 70)
// Assign grade as 'C'
Fgrades[i] = 'C';
// Otherwise checks if average is greater than or equals to 60
else if (avg >= 60)
// Assign grade as 'D'
Fgrades[i] = 'D';
// Otherwise less than 60
else
// Assign grade as 'F'
Fgrades[i] = 'F';
}// End of for loop
}// End of function
// Function to display student names
void printStudents(int COLS, char students[COLS][20])
{
int i = 0;
int numA = COLS;
// Loops till number of columns
for (i = 0; i < numA; ++i)
{
// Displays name
printf("%10s", students[i]);
}
printf("\n");
}// End of function
// Function to read student names from file
void getStudents(int COLS, char students[COLS][20])
{
int i = 0, len = 0;
// Loops till number of columns
for (i = 0; i < COLS; ++i)
{
// Reads name from file and stores it in students i index position
fscanf(fptr, "%s", students[i]);
// Calculates length
len = strlen(students[i]);
// Assigns null at the end
students[i][len-1] = '\0';
}// End of for loop
}// End of function
// Function to display grade of each student
void printGrades(int ROWS, int COLS, int grades[ROWS][COLS])
{
int i = 0, j = 0;
// Loops till number of rows
for (i = 0; i < ROWS; ++i)
{
// Loops till number of columns
for (j = 0; j < COLS; ++j)
{
// Displays grades
printf("%10d", grades[i][j]);
}// End of inner for loop
printf("\n");
}// End of outer for loop
}// End of function
// Function to read grade from the file
void getGrades(int ROWS, int COLS, int grades[ROWS][COLS], char students[COLS][20])
{
int i = 0, j = 0;
// Loops till number of rows
for (i = 0; i < ROWS; ++i)
{
// Loops till number of columns
for (j = 0; j < COLS; ++j)
{
// Reads grade from the file and stores it in matrix grades
fscanf(fptr, "%d", &grades[i][j]);
}// End of inner for loop
}// End of outer for loop
}// End of function

Sample output:

Number of Students 4
Number of Assignment = 5
Joe Kaitli Tyle Shaw
65 79 81 62
46 59 90 84
63 26 93 68
89 95 72 78
91 61 64 98
C D B C