o9 Solutions Interview Questions and Answers for Freshers

The angle between the hour hand and minute hand at 3:15 is 7.5 degrees.

• At 3:00, the hour hand is at the 3 o'clock position, which is 90 degrees.

• In 15 minutes, the minute hand moves 90 degrees (360 degrees divided by 4).

• The hour hand also moves slightly in 15 minutes, covering 7.5 degrees (30 degrees divided by 4).

• Therefore, the angle between the hour hand and minute hand at 3:15 is 7.5 degrees.

Factorial code using recursion

• Recursion is a technique where a function calls itself

• Factorial of a number is the product of all positive integers less than or equal to that number

• To calculate factorial using recursion, the base case is when the number is 0 or 1

• The recursive step is to call the factorial function with the number decremented by 1 and multiply it with the number itself

Trim is used in SQL to remove leading and trailing spaces from a string.

• Trim function is used to remove leading and trailing spaces from a string

• It is commonly used to clean up data before performing comparisons or concatenations

• Syntax: TRIM([LEADING | TRAILING | BOTH] [characters] FROM [string])

• Example: SELECT TRIM(' hello ') as trimmed_string

The task is to reverse a given string that may contain lowercase letters, uppercase letters, digits, and special characters.

• Iterate through the string from the last character to the first character and append each character to a new string.

• Alternatively, you can use built-in string reversal functions or methods available in your programming language.

• To solve the follow-up question with O(1) space complexity, you can use a two-pointer approach. Swap the characters at the start...read more

Fetch data from two tables with a common column without using WHERE keyword.

• Use JOIN keyword to combine the two tables based on the common column.

• Specify the common column in the ON clause of the JOIN statement.

• This will retrieve all the rows where the common column values match in both tables.

Develop a program to compute the factorial of a given integer 'n'.

• Create a function to calculate factorial using a loop or recursion

• Handle edge cases such as negative input or input exceeding constraints

• Return 'Error' if factorial is undefined

• Example: For input 5, output should be 120

Calculate the smallest angle between the hour and minute hands of a clock for a given time.

• Calculate the angles of the hour and minute hands based on the input time.

• Find the absolute difference between the angles of the hour and minute hands.

• Return the smaller angle between the two possible angles.

• Ensure to handle cases where the smaller angle is greater than 180 degrees.