Originally Posted by
fenway81
want it to tell the user they must enter at least two grades.
Have you tried the logic I posted ?
Edit:
I noticed some problems in your code: @line 47 the correct decrement is i-- not i -- (notice the whitespace between i and '--') however, you don't need to decrement i because you're incrementing it in the for loop. @line 117 you forgot to write return 0 (int main expects you return 0):
Code:
int main(void)
{
return 0;
}
consider writting main like that as the first thing you will do in your code
Compare your code with the below one:
Code:
#include <stdio.h>
#include <stdlib.h>
int main(void)
{
/* Declare variables. */
int number_of_grades, grade_total, i, grade, num_invalid_grades;
num_invalid_grades = grade_total = 0;
float average;
/* Output initial greeting and introduce program */
/* --------------------------------------------- */
printf ("This program calculates the average of as many grades as you wish to enter.\n\n");
/* Prompt user for number of grades to be entered. */
/* ------------------------------------------------*/
printf ("First, enter the number of grades to process: ");
scanf ("%i", &number_of_grades);
/* Output appropriate message based on number of grades entered. */
/*---------------------------------------------------------------*/
printf ("\n Now enter the %i grades to be averaged.\n\n", number_of_grades);
for (i = 1; i <= number_of_grades; i++)
{
/* Prompt user for grades. */
/* ----------------------- */
printf ("Enter grade #%d: ", i);
scanf ("%d",&grade);
/* If grade is out of range output error message, otherwise output grade entered.*/
/* ----------------------------------------------------------------------------- */
if (grade > 100 || grade < 0)
{
printf ("*** Invaid entry. Grade must be 0 to 100.***\n");
num_invalid_grades++;
}
else
{
/* Assign values */
/* --------------*/
grade_total = grade_total + grade;
}
} // end for loop
if(num_invalid_grades >= 2)
{
printf("There are more than %d invalid grades\n", num_invalid_grades);
exit(0);
}
/* Calculate average and display output */
/* ------------------------------------ */
average = (float) grade_total / number_of_grades;
printf("\nThe average of the %i grades entered is: %.0f\n\n", number_of_grades, average);
/* Assign values to letter grades */
/* -------------------------------*/
if( average <= 63.0 )
{
printf( "You have a letter grade of F\n" ) ;
}
else if( average <= 66.0 )
{
printf( "You have a letter grade of D\n" ) ;
}
else if( average <= 69.0 )
{
printf( "You have a letter grade of D+\n" ) ;
}
else if( average <= 73.0 )
{
printf( "You have a letter grade of C-\n" ) ;
}
else if( average <= 76.0 )
{
printf( "You have a letter grade of C\n" ) ;
}
else if( average <= 79.0 )
{
printf( "You have a letter grade of C+\n" ) ;
}
else if( average <= 83.0 )
{
printf( "You have a letter grade of B-\n" ) ;
}
else if( average <= 86.0 )
{
printf( "You have a letter grade of B\n" ) ;
}
else if( average <= 89.0 )
{
printf( "You have a letter grade of B+\n" ) ;
}
else if( average <= 93.0 )
{
printf( "You have a letter grade of A-\n" ) ;
}
else
{
printf( "You have a letter grade of A\n" ) ;
}
return 0;
} //end main
