grades ver1.java

import java.util.Scanner; //importing scanner
public class grades { //program begins
    public static void main(String[] args) { //main method begins

        Scanner input = new Scanner (System.in); //scanner declaration

        //variable declaration
        int mark;

        //for the user to input the student's grade
        System.out.println("Please enter the student's mark: ");
        mark = input.nextInt();

        //calls on method letterGrade and outputs the student's grade based on the mark they got
        System.out.println("Student's Grade: " +letterGrade(mark));
    } //main method ends

    //method called letterGrade, it goes through a series of if statements to assign the correct grade to the mark a student receives
    //if the mark isn't valid, an error statement will be shown
    public static String letterGrade(int marks) {
       //variable declaration
        String grade = null;

        //if statements to assign the letter grade to the mark a student gets
        if(marks >= 67 && marks <= 100) {
            grade = "A";
        }
        else
            if(marks >= 60 && marks <= 66) {
                grade = "B+";
            }
            else
                if(marks >= 50 && marks <= 59) {
                    grade = "B";
                }
                else
                    if(marks >= 43 && marks <= 49) {
                        grade = "C";
                    }
                    else
                        if(marks >= 40 && marks <= 42) {
                            grade = "D";
                        }
                        else
                            if(marks >= 0 && marks <= 39) {
                                grade = "Fail";
                            }
                            else {
                                System.out.println("Invalid mark.");
                            } //if statements ends

        //return statement to display in the main method
        return grade;
    } //method letterGrade ends
} //program ends