How do you solve Calculate Delayed Arrival Time on LeetCode?

Calculate Delayed Arrival Time (LeetCode #2651) can be solved using Brute Force or Optimal Solution. The optimal approach is Optimal Solution with O(1) time complexity and O(1) space complexity. Key insight: Using modulo helps to directly handle the wrap-around in 24-hour format.

What is the time complexity of Calculate Delayed Arrival Time?

The optimal solution for Calculate Delayed Arrival Time runs in O(1) time and uses O(1) space. This complexity remains constant as we are performing a fixed number of operations regardless of the input size.

What is the brute force solution for Calculate Delayed Arrival Time?

The brute force approach for Calculate Delayed Arrival Time is Brute Force, with O(1) time complexity and O(1) space complexity. The brute force approach simply adds the arrival time and the delayed time together. If the sum exceeds 24, we can manually adjust it to fit within the 24-hour format. This is straightforward but can be inefficient if we had to perform more complex operations. The optimal Optimal Solution approach improves this to O(1).

What algorithm or data structure is used to solve Calculate Delayed Arrival Time?

Calculate Delayed Arrival Time uses the following concepts: Math. The recommended patterns to study are: Math, Modulo Arithmetic.

What are the interview tips for Calculate Delayed Arrival Time?

Always clarify the input constraints and the expected output format. Think about edge cases, such as maximum delays and wrap-around times. Practice explaining your thought process out loud as you code.

What are common mistakes when solving Calculate Delayed Arrival Time?

Forgetting to use modulo when the sum exceeds 24. Not considering the case where the sum equals 24, which should return 0.

#2651

Calculate Delayed Arrival Time

Easy

MathMathModulo Arithmetic

LeetCode ↗

Approaches

Brute ForceOptimal

Complexity Comparison

	Brute Force	Optimal Solution★
Time	O(1)	O(1)
Space	O(1)	O(1)

💡

Intuition

Time O(1)Space O(1)

The optimal solution leverages the modulo operator to handle the wrap-around effect of the 24-hour format directly. This approach is efficient and avoids unnecessary checks.

⚙️

Algorithm

2 steps

1Step 1: Calculate the new arrival time using the formula (arrivalTime + delayedTime) % 24.
2Step 2: Return the result directly.

solution.py5 lines

1def calculateDelayedArrivalTime(arrivalTime, delayedTime):
2    return (arrivalTime + delayedTime) % 24
3
4# Example usage
5print(calculateDelayedArrivalTime(15, 5))

ℹ

Complexity note: This complexity remains constant as we are performing a fixed number of operations regardless of the input size.

1Using modulo helps to directly handle the wrap-around in 24-hour format.
2Both approaches yield the same result, but the optimal one is more efficient.

Solutions and explanations are original Tejav content. Problem titles © LeetCode — use the LeetCode button above for the full problem statement.