Thread: Massive Menu Monster

I love alliteration. Anyways, to the problem at hand. This is still very much a work in progress (no need to look at the clearly unfinished parts).

The part that I am having trouble with is the functions labeled enter_grade, find_average, and find_letter. The problem lies with that ave bit. It calculates the average of the grades that are found in the array. The problem is i get a cast type error when setting ave=sum/5; This doesn't make any sense to, so I was wondering if it dealt with the sum and pointers which it is adding. If this is the case, please help me fix that part. It is driving me mad.

Code:

#include <stdio.h>
#include <stdlib.h>

int studentgrades [10][5]={0};
int a;

/* Enter grades for a student */
int enter_grades(){
      int j;

      printf ("Enter student number you want to enter grades for: ");
      scanf ("%d", &a);

      printf ("Enter grades for student number %d: ", a);
      for (j = 0; j<5; j++)
          scanf ("%d", *((studentgrades+a)+j));

      printf ("Thank you!\n");

      return 0;
}

/* Find average grades for a particular student */
int find_average(){
      int ave, sum, s;
      printf ("Enter student number you want to get an average for: ");
      scanf ("%d", &a);

      for (s = 0; s<5; s++)
          sum += *((studentgrades+a)+s)
      ave=(sum/5);

      printf ("Average grade for student number %d is:\n", a, ave);

      printf ("Thank you!\n");
}

/* Find letter grade for a particular student */
int find_letter(){
      int ave, sum, s;

      printf ("Enter student number you want to get an average for: ");
      scanf ("%d", &a);

      for (s = 0; s<5; s++)
          sum += *((studentgrades+a)+s)
      ave=(sum/5);

      if (ave<=100 && ave>=90)
          printf ("Letter grade for student number %d: A", a);
      else if (ave<90 && ave>=80)
          printf ("Letter grade for student number %d: B", a);
      else if (ave<80 && ave>=70)
          printf ("Letter grade for student number %d: C", a);
      else if (ave<70 && ave>=60)
          printf ("Letter grade for student number %d: D", a);
      else if (ave<60 && ave>=0)
          printf ("Letter grade for student number %d: E", a);

      printf ("Thank you!\n");
}

/*  Find average grade and letter grade for the whole class */
int avegrade_class()

/*  Find how much would a student need to increase his letter grade */
int increase()

/*displays the menu,select choice*/
int menu()  {
int a;

printf("1.	Enter grades for a student
2.	Find average grades for a particular student
3.	Find letter grade for a particular student
4.	Find average grade and letter grade for the whole class
5.	Find how much would a student need to increase his letter grade
6.	Exit\n
Enter your choice: ");

scanf ("%d", &a);

switch (a)
  {
    case 1: enter_grades(); break;
    case 2: find_average(); break;
    case 3: find_letter(); break;
    case 4: avegrade_class(); break;
    case 5: increase(); break;
    case 6: exit;
  }
}

int main()
{
menu();

      system("PAUSE");
      return 0;
}

Originally posted by Prelude
>not much is changed
Except for declaring functions to return int when they actually return nothing, forgetting a whole slew of semicolons, trying to span string literals across multiple lines and trying to call exit without a parameter list.

>I am not allowed to use [] when accessing elements of an array
What a silly restriction. Here's how you would do it with a two dimensional array:

Code:

*(*(studentgrades + a) + s)

I'm aware its a silly restriction. trust me, i know. Sorry I snapped, but I know a LOT of it isn't done. Thats why I said in the first post to JUST look at the 3 functions I mentioned and for the problems I was adressing at that point.

prelude, I am sitll getting a parse error before the = in the line ave=(sum/5);. I dont understand why ave would be causing a problem?

Woah, didn't even see that. Its always the little things. Thanks.

This is the final code for those who are interested:

Code:

#include <stdio.h>
#include <stdlib.h>

int studentgrades [10][5]={0};
int a;

/* Enter grades for a student */
int enter_grades(){
      int j;

      printf ("\nEnter student number you want to enter grades for: ");
      scanf ("%d", &a);

      printf ("Enter grades for student number %d: ", a);
      for (j = 0; j<5; j++)
          scanf ("%d", *(studentgrades+(a-1))+j);

      printf ("Thank you!\n\n");

      return 0;
}

/* Find average grades for a particular student */
int find_average(){
      int ave=0, sum=0, s;
      printf ("\nEnter student number you want to get an average for: ");
      scanf ("%d", &a);

      for (s = 0; s<5; s++){
          sum += *(*(studentgrades+(a-1))+s);}
      ave=(sum/5);

      printf ("Average grade for student number %d is: %d\n", a, ave);

      printf ("Thank you!\n\n");

      return ave;
}

/* Find letter grade for a particular student */
void find_letter(){
      int ave=0, sum=0, s;

      printf ("\nEnter student number you want to get an average for: ");
      scanf ("%d", &a);

      for (s = 0; s<5; s++){
          sum += *(*(studentgrades+(a-1))+s);}
      ave=(sum/5);

      if (ave<=100 && ave>=90)
          printf ("Letter grade for student number %d: A\n", a);
      else if (ave<90 && ave>=80)
          printf ("Letter grade for student number %d: B\n", a);
      else if (ave<80 && ave>=70)
          printf ("Letter grade for student number %d: C\n", a);
      else if (ave<70 && ave>=60)
          printf ("Letter grade for student number %d: D\n", a);
      else if (ave<60 && ave>=0)
          printf ("Letter grade for student number %d: E\n", a);

      printf ("Thank you!\n\n");
}

/*  Find average grade and letter grade for the whole class */
int avegrade_class() {
     int s,t,i,ave=0, sum=0, empty=0;

     for ( i = 0; i < 10; i++ ) {
         if ( *(*(studentgrades+i)+0) == 0 ) {
            empty = 1;
            break;
            }
     }
      if ( empty )
           return printf("Not all grades entered\n\n");
      else{

      for (s = 0; s<5; s++){
         for (t=0; t<10; t++){
          sum += *(*(studentgrades+t)+s);}
      }

      ave=(sum/50);

      printf ("Average grade for the whole class: %d", ave);

      if (ave<=100 && ave>=90)
          printf ("\nLetter grade for the whole class: A\n");
      else if (ave<90 && ave>=80)
          printf ("\nLetter grade for the whole class: B\n");
      else if (ave<80 && ave>=70)
          printf ("\nLetter grade for the whole class: C\n");
      else if (ave<70 && ave>=60)
          printf ("\nLetter grade for the whole class: D\n");
      else if (ave<60 && ave>=0)
          printf ("\nLetter grade for the whole class: E\n");

      printf ("Thank you!\n\n");
      }

}
/*  Find how much would a student need to increase his letter grade */
void increase() {
      int sum=0, s, grade=0;

      printf ("Enter student number: ");
      scanf ("%d", &a);

      for (s = 0; s<5; s++){
          sum += *(*(studentgrades+(a-1))+s);}

      if (sum>=450)
        printf ("Letter grade can not be increased, already an A.\n");
      else if (sum<450 && sum>=400){
        grade=450-sum;
        printf ("Number of points needed to increase letter grade: %d\n", grade);}
      else if (sum<400 && sum>=350){
        grade=400-sum;
        printf ("Number of points needed to increase letter grade: %d\n", grade);}
      else if (sum<350 && sum>=300){
        grade=350-sum;
        printf ("Number of points needed to increase letter grade: %d\n", grade);}
      else if (sum<300){
        grade=300-sum;
        printf ("Number of points needed to increase letter grade: %d\n", grade);}

      printf ("Thank you!\n\n");
}

/*displays the menu,select choice*/
int menu()  {
int a;

printf("1.	Enter grades for a student\n"
       "2.	Find average grades for a particular student\n"
       "3.	Find letter grade for a particular student\n"
       "4.	Find average grade and letter grade for the whole class\n"
       "5.	Find how much would a student need to increase his letter grade\n"
       "6.	Exit\n"
       "Enter your choice: ");

scanf ("%d", &a);

switch (a)
  {
    case 1: enter_grades(); break;
    case 2: find_average(); break;
    case 3: find_letter(); break;
    case 4: avegrade_class(); break;
    case 5: increase(); break;
    case 6: exit(0);
  }
}

int main()
{
while(1) {
      menu();
}
      system("PAUSE");
      return 0;
}