06. డెసిషన్ మేకింగ్ — if, else-if, else & టెర్నరీ ఆపరేటర్ (Decision Making in Java)

public class StudentGradeAnalyzer {
    public static void main(String[] args) {
        String studentName = "భవాని శంకర్";
        int mathMarks    = 92;
        int physicsMarks = 88;
        int chemMarks    = 85;

        int totalMarks = mathMarks + physicsMarks + chemMarks;
        double averagePercentage = totalMarks / 3.0;

        System.out.println("==================================================");
        System.out.println("       ACADEMIC PERFORMANCE & GRADE REPORT       ");
        System.out.println("==================================================");
        System.out.println("Student Name : " + studentName);
        System.out.printf("Total Marks  : %d / 300%n", totalMarks);
        System.out.printf("Average %%    : %.2f%%%n", averagePercentage);
        System.out.println("--------------------------------------------------");

        // else-if Ladder Evaluation
        String finalGrade;
        String meritStatus;

        if (averagePercentage >= 90.0) {
            finalGrade = "A+ (Distinction)";
            meritStatus = "Gold Medal Candidate";
        } else if (averagePercentage >= 75.0) {
            finalGrade = "A (First Class with Honors)";
            meritStatus = "Dean's Honor List";
        } else if (averagePercentage >= 60.0) {
            finalGrade = "B (First Class)";
            meritStatus = "Qualified for Placement";
        } else if (averagePercentage >= 40.0) {
            finalGrade = "C (Pass Class)";
            meritStatus = "Eligible for Graduation";
        } else {
            finalGrade = "F (Failed)";
            meritStatus = "Supplementary Required";
        }

        System.out.println("Final Grade  : " + finalGrade);
        System.out.println("Merit Status : " + meritStatus);
        System.out.println("==================================================");
    }
}

public class LoanApprovalEngine {
    public static void main(String[] args) {
        String applicantName = "రాజేష్ వర్మ";
        int cibilScore       = 760;
        double monthlySalary = 65000.0;
        double existingEmis  = 15000.0;
        int age              = 32;

        System.out.println("--------------------------------------------------");
        System.out.println("       HOME LOAN UNDERWRITING & APPROVAL         ");
        System.out.println("--------------------------------------------------");
        System.out.println("Applicant : " + applicantName + " (Age: " + age + ")");
        System.out.println("CIBIL     : " + cibilScore);
        System.out.printf("Salary    : ₹ %,.2f | Existing EMIs: ₹ %,.2f%n", monthlySalary, existingEmis);
        System.out.println("--------------------------------------------------");

        // Multi-tier Nested Decision Structure
        if (age >= 21 && age <= 60) {
            if (cibilScore >= 750) {
                double maxAllowableEmi = monthlySalary * 0.50; // 50% FOIR limit
                double disposableEmi = maxAllowableEmi - existingEmis;

                if (disposableEmi >= 15000.0) {
                    System.out.println("Decision : [APPROVED] Pre-approved Loan Limit: ₹ 45,00,000");
                    System.out.printf("Max EMI  : Up to ₹ %,.2f per month at 8.4%% ROI%n", disposableEmi);
                } else {
                    System.out.println("Decision : [REJECTED] High Debt-to-Income ratio (FOIR exceeded).");
                }
            } else if (cibilScore >= 650) {
                System.out.println("Decision : [MANUAL REVIEW] Requires Co-applicant or Collateral.");
            } else {
                System.out.println("Decision : [REJECTED] Low Credit Score below minimum cutoff (650).");
            }
        } else {
            System.out.println("Decision : [REJECTED] Age not within allowable underwriting bracket.");
        }
        System.out.println("--------------------------------------------------");
    }
}

public class AtmCashDispenserEngine {
    public static void main(String[] args) {
        int storedPin         = 4829;
        int enteredPin        = 4829;
        int accountBalance    = 42500;
        int withdrawalRequest = 8500;
        int dailyWithdrawLimit = 25000;
        int dailyWithdrawnToday = 10000;

        System.out.println("==================================================");
        System.out.println("        HYDERABAD METRO BANK ATM DISPENSER        ");
        System.out.println("==================================================");

        // Security Authentication
        if (enteredPin != storedPin) {
            System.out.println("[SECURITY ALERT] Invalid PIN entered! Card session terminated.");
            return;
        }

        System.out.println("[STATUS] PIN Verified. Authenticated Account Holder.");

        // Checking withdrawal validations via Short-circuit & Nested Logic
        if (withdrawalRequest <= 0) {
            System.out.println("[ERROR] Invalid withdrawal amount. Must be greater than 0.");
        } else if (withdrawalRequest % 100 != 0) {
            System.out.println("[ERROR] Amount must be in multiples of ₹ 100 or ₹ 500.");
        } else if (withdrawalRequest > accountBalance) {
            System.out.println("[DECLINED] Insufficient account balance! Current: ₹ " + accountBalance);
        } else if ((dailyWithdrawnToday + withdrawalRequest) > dailyWithdrawLimit) {
            int remainingDailyLimit = dailyWithdrawLimit - dailyWithdrawnToday;
            System.out.println("[DECLINED] Exceeds daily ATM limit! Max remaining today: ₹ " + remainingDailyLimit);
        } else {
            // Dispensing cash
            accountBalance -= withdrawalRequest;
            dailyWithdrawnToday += withdrawalRequest;

            int count500 = withdrawalRequest / 500;
            int count100 = (withdrawalRequest % 500) / 100;

            System.out.println("--------------------------------------------------");
            System.out.println("Transaction Status: [SUCCESS] Cash Dispensed!");
            System.out.printf("  ₹ 500 Currency Notes : %d note(s)%n", count500);
            System.out.printf("  ₹ 100 Currency Notes : %d note(s)%n", count100);
            System.out.println("--------------------------------------------------");
            System.out.printf("  Total Dispensed  : ₹ %,d%n", withdrawalRequest);
            System.out.printf("  Remaining Balance: ₹ %,d%n", accountBalance);
        }
        System.out.println("==================================================");
    }
}