Java Program to Create a Grading System (With Explanation & Dry Run)

Introduction

A Grading System program in Java is one of the most common programs asked in BCA exams, school practicals, and interviews.
This program uses conditional statements (if-else) to assign grades based on marks obtained by a student.

In this article, you will learn how to make a grading system in Java with a clear explanation and dry run.

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📝 What Is a Grading System?

A grading system assigns a grade to a student based on their marks.

Example Grading Criteria

Marks Range	Grade
90 – 100	A
75 – 89	B
60 – 74	C
40 – 59	D
Below 40	Fail

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🧠 Logic Used

• Take marks as input

• Use if-else if ladder

• Check marks range

• Display corresponding grade

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🧩 Algorithm for Grading System

1. Start

2. Read marks

3. If marks ≥ 90 → Grade A

4. Else if marks ≥ 75 → Grade B

5. Else if marks ≥ 60 → Grade C

6. Else if marks ≥ 40 → Grade D

7. Else → Fail

8. End

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💻 Java Program for Grading System

import java.util.Scanner;

public class GradingSystem {
    public static void main(String[] args) {
        int marks;

        Scanner sc = new Scanner(System.in);
        System.out.print("Enter marks: ");
        marks = sc.nextInt();

        if (marks >= 90 && marks <= 100) {
            System.out.println("Grade: A");
        } else if (marks >= 75) {
            System.out.println("Grade: B");
        } else if (marks >= 60) {
            System.out.println("Grade: C");
        } else if (marks >= 40) {
            System.out.println("Grade: D");
        } else if (marks >= 0) {
            System.out.println("Fail");
        } else {
            System.out.println("Invalid marks");
        }
    }
}

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🧪 Dry Run

Input

marks = 82

Step-by-Step Execution

• marks ≥ 90 → ❌

• marks ≥ 75 → ✅

• Output → Grade B

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🖥️ Output

Enter marks: 82
Grade: B

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📌 Another Example

Input

marks = 35

Output

Fail

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🎯 Important Points for Exams

• Uses if-else if ladder

• Always check highest condition first

• Handle invalid marks

• Time Complexity: O(1)