help w/ storing/scanning numbers in arrays

• 11-17-2010, 08:05 PM
clemsontigers
help w/ storing/scanning numbers in arrays
these are my instructions
A Computer Technology Instructor has a small class of 10 students. The instructor evaluates the performance of students in the class by administering 2 midterm tests and a Final Exam.

Write a program that prompts the instructor to enter the 10 grades of Midterm 1 and store these numbers in an array. Next prompt for the 10 grades of Midterm2 and store these numbers in a different array. Next prompt for the 10 grades of the Final Exam and store these in a different array. Next add Midterm1 to Midterm2 to Final and store the total of grades in a different array. Next, scan the array that has the totals and identify the minimum grade and maximum grade. Inform the instructor of the minimum grade and maximum grade.

Note : do not assume that the grades are in the range 0 to 100. Your program should function properly whether the grades are in the range 0 to 100 or any other range.
*I'm using eclipse btw

it prompts me to enter my numbers and stores them in the array correctly but when it tells me what my lowest score it says 0.0 and my highest score is 0.0...also, im not sure exactly how to add the total of midterm1 to midterm2 to final exam or how scan the array..and it repeats my highest and lowest score

so far this is my output after i enter the grades

You have entered following grades for midTerm2: [2.0, 2.0, 2.0, 2.0, 2.0, 2.0, 2.0, 2.0, 2.0, 2.0]
You have entered following grades for Final Exam: [2.0, 2.0, 2.0, 2.0, 2.0, 2.0, 2.0, 2.0, 2.0, 2.0]

here is my code

Code:

```import java.util.Scanner; import java.util.Arrays; public class Assign9_Roberts {         public static void main(String[] args)         {                 //input scanner                 Scanner input = new Scanner(System.in);                         //Prompt User for midterm1 grades                         double[]midTerm1= new double [10];             for (int A = 0; A <midTerm1.length; A++){                 System.out.println("Please enter MidTerm1 grade:");                 midTerm1[A] = input.nextInt();             }             System.out.println("Now");           //Prompt User for midterm2 grades             double[]midTerm2=new double[10];             for(int B=0; B<midTerm2.length;B++){               System.out.println("Please enter a MidTerm2 grade:");               midTerm2[B] = input.nextInt();             }             System.out.println("Now");           //Prompt User for Final Exam grades             double[]finalExam = new double[10];             for(int C = 0; C<finalExam.length; C++){                     System.out.println("Please enter a Final Exam grade:");                     finalExam[C] = input.nextInt();             }             int [] grades = new int [10];                         int max = 0;                                           //Display highest score                         for (int t = 0; t < grades.length; t ++)                         {                                 if (grades[t] > max)                                 {                                         max = grades[t];                                 }                                                                 System.out.print("Your highest test score is: " + max);                                                         //Display lowest score                         int min = 0;                                 if(grades[t] < min)                                 {                                         min = grades[t];                                 }                                 System.out.print("Your lowest test score is: " + min);                             }                  System.out.print("You have entered following grades for midTerm1:    ");           System.out.println(Arrays.toString(midTerm1));           System.out.print("You have entered following grades for midTerm2:    ");           System.out.println(Arrays.toString(midTerm2));           System.out.print("You have entered following grades for Final Exam:  ");           System.out.println(Arrays.toString(finalExam));                         }                         }```
also this is cross posted
http://www.javaprogrammingforums.com...html#post21185
• 11-17-2010, 08:09 PM
Allspark
When posting code can you please use the code formatter. Put
Code:

` before your code and then`
at the end. It makes it easier to debug.
• 11-17-2010, 08:15 PM
pbrockway2
Code:

```//Display highest score for (int t = 0; t < grades.length; t ++) {   if (grades[t] > max)   {       max = grades[t];   }                 System.out.print("Your highest test score is: " + max);                 //Display lowest score   int min = 0;   if(grades[t] < min)   {       min = grades[t];   }   System.out.print("Your lowest test score is: " + min); }```

You won't know about the minimum and maximum scores until after the for loop has finished and checked everybody's score. So move the System.out.print() statements to after the for loop.
• 11-17-2010, 08:16 PM
pbrockway2
On the formatting, I think Allspark meant: put [CODE] before your code and the [/CODE] at the end.
• 11-17-2010, 08:28 PM
JosAH
Quote:

Originally Posted by Allspark
When posting code can you please use the code formatter. Put
Code:

` before your code and then`
at the end. It makes it easier to debug.

That was written as:

Put [code] before your code and then [/code] at the end.

And the previous line was written using a little trick to mislead that stupid forum software. ;-)

kind regards,

Jos
• 11-18-2010, 02:49 AM
clemsontigers
here is my updated code and after i run it and enter a number it gives me this error

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 10
at Assign9_Roberts.main(Assign9_Roberts.java:29)

Code:

```import java.util.Scanner; import java.util.Arrays; public class Assign9_Roberts {         public static void main(String[] args)         {                 //input scanner                 Scanner input = new Scanner(System.in);                   double[] grades = new double[10];               double[] midTerm1 = new double[10];               double[] midTerm2 = new double[10];               double[] finalExam = new double[10];                                             // add midterm1 , midterm2 and final grades and store them in grade array                 for (int i=0; i<finalExam.length; i++ ) {                     grades[i] = midTerm1[i] + midTerm2[i] + finalExam[i];                 }                 System.out.println("Please enter a MidTerm1 grade:");             midTerm1[10] = input.nextDouble();                                     System.out.println("Now");             for(int B=0; B<midTerm2.length;B++){             }             System.out.println("Please enter a MidTerm2 grade:");             midTerm2[10] = input.nextDouble();                         System.out.println("Now");             for(int C = 0; C<finalExam.length; C++){             }             System.out.println("Please enter a Final Exam grade:");                 finalExam[10] = input.nextDouble();                             double max = grades[0];                 double min = grades[0];                                         //Display highest score                 for (int t = 0; t < grades.length; t ++)                 {                   if (grades[t] > max)                   {                       max = grades[t];                   }                                                 System.out.print("Your highest test score is: " + max);                                                 //Display lowest score                       if(grades[t] < min)                   {                       min = grades[t];                   }                   System.out.print("Your lowest test score is: " + min);                 }                  System.out.print("You have entered following grades for midTerm1:    ");           System.out.println(Arrays.toString(midTerm1));           System.out.print("You have entered following grades for midTerm2:    ");           System.out.println(Arrays.toString(midTerm2));           System.out.print("You have entered following grades for Final Exam:  ");           System.out.println(Arrays.toString(finalExam));                         }                         }```
• 11-18-2010, 02:55 AM
al_Marshy_1981
Code:

` midTerm1[10] = input.nextDouble();`
midTerm1[10] does not exist, arrays(and computers)begin counting from 0, if you want the tenth element use 9, 0-9 is ten elements.
• 11-18-2010, 03:55 AM
clemsontigers
ok i changed that..thanks, but im still getting the same error..here's my updated code

Code:

``` import java.util.Scanner; import java.util.Arrays; public class Assign9_Roberts {         public static void main(String[] args)         {                 //input scanner                 Scanner input = new Scanner(System.in);                   double[] grades = new double[9];               double[] midTerm1 = new double[9];               double[] midTerm2 = new double[9];               double[] finalExam = new double[9];                                             // add midterm1 , midterm2 and final grades and store them in grade array                 for (int i=0; i<finalExam.length; i++ ) {                     grades[i] = midTerm1[i] + midTerm2[i] + finalExam[i];                 }                 System.out.println("Please enter a MidTerm1 grade:");             midTerm1[9] = input.nextDouble();                                     System.out.println("Now");             for(int B=0; B<midTerm2.length;B++){             }             System.out.println("Please enter a MidTerm2 grade:");             midTerm2[9] = input.nextDouble();                         System.out.println("Now");             for(int C = 0; C<finalExam.length; C++){             }             System.out.println("Please enter a Final Exam grade:");                 finalExam[9] = input.nextDouble();                             double max = grades[0];                 double min = grades[0];                                         //Display highest score                 for (int t = 0; t < grades.length; t ++)                 {                   if (grades[t] > max)                   {                       max = grades[t];                   }                                                 System.out.print("Your highest test score is: " + max);                                                 //Display lowest score                       if(grades[t] < min)                   {                       min = grades[t];                   }                   System.out.print("Your lowest test score is: " + min);                 }                  System.out.print("You have entered following grades for midTerm1:    ");           System.out.println(Arrays.toString(midTerm1));           System.out.print("You have entered following grades for midTerm2:    ");           System.out.println(Arrays.toString(midTerm2));           System.out.print("You have entered following grades for Final Exam:  ");           System.out.println(Arrays.toString(finalExam));                         }                         }```
• 11-18-2010, 03:56 AM
Fubarable
What is the exact error message and please show which line is causing it.
• 11-18-2010, 04:17 AM
mine0926
You just declare your arrays with a lenght of 9, index in array starts with zero meaning when
you declare
Code:

`    double[] midTerm1 = new double[9];`
it means that the maximum index is 8.
Code:

`    midTerm1[8] = something;`

Look at this line. You put 9 in midTerm1 index which gives you error because 9th midTerm1 is
actually midTerm1[8].
Code:

`    midTerm1[9] = input.nextDouble();`
• 11-18-2010, 04:50 AM
clemsontigers
also, trying to submit this assignment within and hour so a quick response is greatly appreciated..thanks

i updated my code and while im not getting the same error its only allowing me to enter 3 numbers and giving me this out put.

100
Now
90
Now
90
Your highest test score is: 0.0Your lowest test score is: 0.0Your highest test score is: 0.0Your lowest test score is: 0.0Your highest test score is: 0.0Your lowest test score is: 0.0Your highest test score is: 0.0Your lowest test score is: 0.0Your highest test score is: 0.0Your lowest test score is: 0.0Your highest test score is: 0.0Your lowest test score is: 0.0Your highest test score is: 0.0Your lowest test score is: 0.0Your highest test score is: 0.0Your lowest test score is: 0.0Your highest test score is: 0.0Your lowest test score is: 0.0You have entered following grades for midTerm1: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 100.0]
You have entered following grades for midTerm2: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 90.0]
You have entered following grades for Final Exam: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 90.0]

Code:

``` import java.util.Scanner; import java.util.Arrays; public class Assign9_Roberts {         public static void main(String[] args)         {                 //input scanner                 Scanner input = new Scanner(System.in);                   double[] grades = new double[9];               double[] midTerm1 = new double[9];               double[] midTerm2 = new double[9];               double[] finalExam = new double[9];                                             // add midterm1 , midterm2 and final grades and store them in grade array                 for (int i=0; i<finalExam.length; i++ ) {                     grades[i] = midTerm1[i] + midTerm2[i] + finalExam[i];                 }                 System.out.println("Please enter a MidTerm1 grade:");             midTerm1[8] = input.nextDouble();                                     System.out.println("Now");             for(int B=0; B<midTerm2.length;B++){             }             System.out.println("Please enter a MidTerm2 grade:");             midTerm2[8] = input.nextDouble();                         System.out.println("Now");             for(int C = 0; C<finalExam.length; C++){             }             System.out.println("Please enter a Final Exam grade:");                 finalExam[8] = input.nextDouble();                             double max = grades[0];                 double min = grades[0];                                         //Display highest score                 for (int t = 0; t < grades.length; t ++)                 {                   if (grades[t] > max)                   {                       max = grades[t];                   }                                                 System.out.print("Your highest test score is: " + max);                                                 //Display lowest score                       if(grades[t] < min)                   {                       min = grades[t];                   }                   System.out.print("Your lowest test score is: " + min);                 }                  System.out.print("You have entered following grades for midTerm1:    ");           System.out.println(Arrays.toString(midTerm1));           System.out.print("You have entered following grades for midTerm2:    ");           System.out.println(Arrays.toString(midTerm2));           System.out.print("You have entered following grades for Final Exam:  ");           System.out.println(Arrays.toString(finalExam));                         }                         }```
• 11-18-2010, 05:40 AM
mine0926
As stated in instruction, prompt the user to enter 10 grades each for midTerm1, midTerm2 and FinalExam. After the user input these that is the time you compute its total.

But what you did is,
Code:

```[b]You compute the total first[/b]                 for (int i=0; i<finalExam.length; i++ ) {                     grades[i] = midTerm1[i] + midTerm2[i] + finalExam[i];                 }```

Then prompt the user to enter midTerm grades only ONCE.
Code:

```                System.out.println("Please enter a MidTerm1 grade:");             midTerm1[8] = input.nextDouble();                                     System.out.println("Now");             for(int B=0; B<midTerm2.length;B++){             }             System.out.println("Please enter a MidTerm2 grade:");             midTerm2[8] = input.nextDouble();                         System.out.println("Now");             for(int C = 0; C<finalExam.length; C++){             }             System.out.println("Please enter a Final Exam grade:");                 finalExam[8] = input.nextDouble();```

and pass the value to the last index of you array
Code:

```            midTerm1[8] = input.nextDouble();             midTerm2[8] = input.nextDouble();             FinalExam[8] = input.nextDouble();```
• 11-18-2010, 05:45 AM
clemsontigers
prolly sound like an idiot but im not really sure what to do now
• 11-18-2010, 05:50 AM
mine0926
Your first post to ask the user to enter the grades is correct but not the array, ok...

Also you have logical error in getting the minimum grade. But maybe we can discuss that after you fix the "asking for grades 10x"...

:)
• 11-18-2010, 05:59 AM
mine0926
OK, I read your first/orignal post, it is perfectly correct. The only error is
```import java.util.Scanner; import java.util.Arrays; public class Assign9_Roberts {  public static void main(String[] args)     {         //input scanner         Scanner input = new Scanner(System.in);         //Prompt User for midterm1 grades         double[]midTerm1= new double [10];         for (int A = 0; A <midTerm1.length; A++){             System.out.println("Please enter MidTerm1 grade:");             midTerm1[A] = input.nextInt();         }         System.out.println("Now");         //Prompt User for midterm2 grades         double[]midTerm2=new double[10];         for(int B=0; B<midTerm2.length;B++){             System.out.println("Please enter a MidTerm2 grade:");             midTerm2[B] = input.nextInt();         }         System.out.println("Now");         //Prompt User for Final Exam grades         double[]finalExam = new double[10];         for(int C = 0; C<finalExam.length; C++){             System.out.println("Please enter a Final Exam grade:");             finalExam[C] = input.nextInt();         }         int [] grades = new int [10];         [b]         int max = 0;         //Display highest score         for (int t = 0; t < grades.length; t ++)         {             if (grades[t] > max)             {  max = grades[t];             }             int min = 0;             //Display lowest score             if(grades[t] < min)             {                 min = grades[t];             }         }         System.out.print("Your highest test score is: " + max);         System.out.print("Your lowest test score is: " + min);         System.out.print("You have entered following grades for midTerm1:    ");         System.out.println(Arrays.toString(midTerm1));         System.out.print("You have entered following grades for midTerm2:    ");         System.out.println(Arrays.toString(midTerm2));         System.out.print("You have entered following grades for Final Exam:  ");         System.out.println(Arrays.toString(finalExam));         [/b]     } }```