Using nested if statements in Java to calculate letter grade from numeric input

Question

My homework task is to create a program that accepts a numeric input between 0-100 and returns a letter and +/- if appropriate. We are to accomplish this using nested if statements. I attempted to create an outer if statement that would return a letter grade followed by nested if statements that would return the +/- part.

The output I receive varies from 6543 to 00. I have copied my code below. Could anyone point me in the right direction? I feel like this is a bit of a mess.

import java.util.Scanner;
import java.lang.Math;

public class Grade {
    public static void main (String [] args) {

        Scanner scan = new Scanner (System.in);

//Prompt user to enter grade

        System.out.println("Please enter your grade ");
        int grade = scan.nextInt();
        byte grade1 = (0);
        byte note = (0);

//Determine letter and +/-

        if ( grade <= 100 && grade >= 90 ) {
            grade1 = 'A';
            if (grade <= 100 && grade >= 96) {
                note = '+';
            }
            else if (grade <= 94 && grade >= 90) {
                note = '-';
            }
        }

        else if ( grade <= 80 && grade >= 89 ) {
            grade1 = 'B';
            if (grade <= 89 && grade >= 86) {
                note = '+';
            }
            else if (grade <= 84 && grade >= 80) {
                note = '-';
            }
        }

        else if ( grade <= 70 && grade >= 79 ) {
            grade1 = 'C';
            if (grade <= 79 && grade >= 76) {
                note = '+';
            }
            else if (grade <= 74 && grade >= 70) {
                note = '-';
            }
        }        

        else if ( grade <= 60 && grade >= 69 ) {
            grade1 = 'D';
            if (grade <= 69 && grade >= 66) {
                note = '+';
            }
            else if (grade <= 64 && grade >= 60) {
                note = '-';
            }
        }

        else if ( grade <= 59 ) {
            grade1 = 'F';
        }

//Print out grade

        System.out.println("You have a " + grade1 + note + " in the class.");

// End program
        scan.close();
        System.exit(0);        
    }
}

Answer 1

else if ( grade <= 80 && grade >= 89 ) {

Take a moment to think about that one. I think you intend for e.g. 85 to cause this if to trigger, right.

Is 85 lower or equal than 80? I don't think it is. It's not 89 or higher either. In fact, no number will ever satisfy this condition.

Flip your < and > signs :)

Second issue is that grade1 and note are bytes, which are numbers, so "You have a " + (some number) + (some other number) + " in the class" is always going to print "You have a 12345677 in the class", that is, those things are, well, numbers. I have no idea why you thought byte was going to work out here. Give it another try with char.