Problem Statement
Sum of Digits Until Single Digit (Add Digits)
Question Details: Given a number (e.g., 38), continuously add all its digits until the result is a single digit.
Example: 38 ➔ 3 + 8 = 11 ➔ 1 + 1 = 2. Output = 2.
Java Solution
public class Main {
public static int addDigits(int num) {
while (num >= 10) {
int sum = 0;
while (num > 0) {
sum += num % 10;
num /= 10;
}
num = sum;
}
return num;
}
public static void main(String[] args) {
System.out.println(“Output: ” + addDigits(38)); // Output: 2
}
}
Python Solution
def add_digits(num: int) -> int:
while num >= 10:
num = sum(int(digit) for digit in str(num))
return num
print(“Output:”, add_digits(38)) # Output: 2
HTML & CSS Requirement
Target Specific Input Types and Apply Padding
Question Details: Target an HTML input element specifically by its type attribute in CSS and apply custom padding styling.
HTML Structure
<!– Text Input Element –>
<input type=”text” class=”custom-input” placeholder=”Enter text here…”>
CSS Solution
/* Target specific input type using attribute selector */
input[type=”text”] {
padding: 16px 20px; /* Applies vertical and horizontal padding */
border: 2px solid #000033;
border-radius: 6px;
font-size: 14px;
}
JavaScript Validation
Password Match & Validation Logic
Question Details: On clicking submit:
1. If empty, display “Password is not there”.
2. If passwords match, display the matched password.
3. If passwords differ, display “Wrong password” using textContent.
JavaScript Solution Code
function validatePassword() {
const password = document.getElementById(“passInput”).value.trim();
const confirmPassword = document.getElementById(“confirmPassInput”).value.trim();
const resultMsg = document.getElementById(“resultMsg”);
if (password === “” || confirmPassword === “”) {
resultMsg.textContent = “Password is not there”;
resultMsg.style.color = “#dc2626”;
} else if (password === confirmPassword) {
resultMsg.textContent = “Password matched: ” + password;
resultMsg.style.color = “#16a34a”;
} else {
resultMsg.textContent = “Wrong password”;
resultMsg.style.color = “#dc2626”;
}
}
Database Query
3-Table LEFT JOIN Query
Question Details: Join three tables using LEFT JOIN to extract student details along with course and assessment information.
SQL Query Solution
SELECT
s.student_id,
s.student_name,
c.course_name,
a.score,
a.status
FROM students s
LEFT JOIN enrollments e ON s.student_id = e.student_id
LEFT JOIN courses c ON e.course_id = c.course_id
LEFT JOIN assessments a ON s.student_id = a.student_id;
