Need help with Java Grades. (While Loop String input)

[Energizer100]

Hey. I'm new to Java and I'm trying to make a grades program for a class assignment. This is what I have so far.


[CODE=java]import java.util.Scann er;
import static java.lang.Syste m.out;

public class Grades//Creates Class
{
public static void main(String[] args)
{
Scanner myScanner = new Scanner(System. in);
String grade;
double counter1 = 0.0;//Variables
double counter2 = 0.0;
char i;
char F;

out.println("En ter your grade: ");
grade = myScanner.nextL ine();

while(grade != "q"){

out.println("En ter your grade. Enter q to see whether or not you are eligible: ");
grade = myScanner.nextL ine();

if (grade == "A")
{
counter1 += 4.0;
counter2++;
}
else if (grade == "B")
{
counter1 += 3.0;
counter2++;
}
else if (grade == "C")
{
counter1 += 2.0;
counter2++;
}
else if (grade == "D")
{
counter1 += 1.0;
counter2++;
}
else if (grade == "F")
{
i = 'F';
counter1 += 0.0;
counter2++;
}

}

if (grade == "q"){

if (counter2 < 4){
System.out.prin tln("Ineligible , taking less than 4 classes");
}
else if ((counter2 >= 4) && (counter1/counter2 < 2.0)){
System.out.prin tln("Ineligible , gpa below 2.0");
}
else if (i == 'F')
{
if ((counter2 >= 4) && (counter1 / counter2 < 2.0)){
System.out.prin tln("Inelegible , gpa below 2.0 and has F grade");
}
else ((counter2 >= 4) && (counter1 / counter2 >= 2.0)){
System.out.prin tln("Inelegible , gpa above 2.0 but has F grade");
}
}

else{
System.out.prin tln("GPA = " + (counter1/counter2) + " Eligible");
}
}
}
}[/CODE]



It says stuff like 'i' is not initialized. But when I delete that line of code(I need it there though, just testing it), the string input thing won't stop when I enter q.

[Dameon99]

Hey. I'm new to Java and I'm trying to make a grades program for a class assignment. This is what I have so far.


import java.util.Scann er;
import static java.lang.Syste m.out;

public class Grades//Creates Class
{
public static void main(String[] args)
{
Scanner myScanner = new Scanner(System. in);
String grade;
double counter1 = 0.0;//Variables
double counter2 = 0.0;
char i;
char F;

out.println("En ter your grade: ");
grade = myScanner.nextL ine();

while(grade != "q"){

out.println("En ter your grade. Enter q to see whether or not you are eligible: ");
grade = myScanner.nextL ine();

if (grade == "A")
{
counter1 += 4.0;
counter2++;
}
else if (grade == "B")
{
counter1 += 3.0;
counter2++;
}
else if (grade == "C")
{
counter1 += 2.0;
counter2++;
}
else if (grade == "D")
{
counter1 += 1.0;
counter2++;
}
else if (grade == "F")
{
i = 'F';
counter1 += 0.0;
counter2++;
}

}

if (grade == "q"){

if (counter2 < 4){
System.out.prin tln("Ineligible , taking less than 4 classes");
}
else if ((counter2 >= 4) && (counter1/counter2 < 2.0)){
System.out.prin tln("Ineligible , gpa below 2.0");
}
else if (i == 'F')
{
if ((counter2 >= 4) && (counter1 / counter2 < 2.0)){
System.out.prin tln("Inelegible , gpa below 2.0 and has F grade");
}
else ((counter2 >= 4) && (counter1 / counter2 >= 2.0)){
System.out.prin tln("Inelegible , gpa above 2.0 but has F grade");
}
}

else{
System.out.prin tln("GPA = " + (counter1/counter2) + " Eligible");
}
}
}
}



It says stuff like 'i' is not initialized. But when I delete that line of code(I need it there though, just testing it), the string input thing won't stop when I enter q.

All variables should be initialised when you decalare them.

ie int i = 0;

i will be changed later in your code but this would initialise the variable and keep your compiler happy :-)

[Energizer100]

All variables should be initialised when you decalare them.

ie int i = 0;

i will be changed later in your code but this would initialise the variable and keep your compiler happy :-)

Ah, I see now.

I'm also making another grades program, but it has a do while loop and a while loop. But I'm having problems with 'i'. See, when the loop runs, and the user enters 'i', I want 'i' to store the value 'F'. So in my while loop, if 'i' was equal to 'F', it would go to a different if-else statement.


import java.io.*;

[CODE=java]public class Grade
{
public static void main(String[] args) throws IOException
{
BufferedReader br = new BufferedReader( new InputStreamRead er(System.in));
String inData;
double grade = 0;
double counter1 = 0.0;

do
{
System.out.prin tln("Enter your grade. Enter q to quit");
inData = br.readLine();

if (inData.equals( "A"))
{
grade = grade + 4.0;
counter1++;
}
else if (inData.equals( "B"))
{
grade = grade + 3.0;
counter1++;
}
else if (inData.equals( "C"))
{
grade = grade + 2.0;
counter1++;
}
else if (inData.equals( "D"))
{
grade = grade + 1.0;
counter1++;
}
else if (inData.equals( "F"))
{
grade = grade + 0.0;
counter1++;
}
}

while (!inData.equals ("q"));{

if (counter1 < 4){
System.out.prin tln("Ineligible , taking less than 4 classes");
}
else if ((counter1 >= 4) && (grade / counter1 < 2.0)){
System.out.prin tln("Ineligible , gpa below 2.0");
}

else{
System.out.prin tln("GPA = " + (grade/counter1) + " Eligible");
}
}
}
}[/CODE]

[Energizer100]

Ah, I see now.

I'm also making another grades program, but it has a do while loop and a while loop. But I'm having problems with 'i'. See, when the loop runs, and the user enters 'i', I want 'i' to store the value 'F'. So in my while loop, if 'i' was equal to 'F', it would go to a different if-else statement.


import java.io.*;

public class Grade
{
public static void main(String[] args) throws IOException
{
BufferedReader br = new BufferedReader( new InputStreamRead er(System.in));
String inData;
double grade = 0;
double counter1 = 0.0;

do
{
System.out.prin tln("Enter your grade. Enter q to quit");
inData = br.readLine();

if (inData.equals( "A"))
{
grade = grade + 4.0;
counter1++;
}
else if (inData.equals( "B"))
{
grade = grade + 3.0;
counter1++;
}
else if (inData.equals( "C"))
{
grade = grade + 2.0;
counter1++;
}
else if (inData.equals( "D"))
{
grade = grade + 1.0;
counter1++;
}
else if (inData.equals( "F"))
{
grade = grade + 0.0;
counter1++;
}
}

while (!inData.equals ("q"));{

if (counter1 < 4){
System.out.prin tln("Ineligible , taking less than 4 classes");
}
else if ((counter1 >= 4) && (grade / counter1 < 2.0)){
System.out.prin tln("Ineligible , gpa below 2.0");
}

else{
System.out.prin tln("GPA = " + (grade/counter1) + " Eligible");
}
}
}
}

nvr mind. I found out the reason. Thank you so much for the help.