#495

Teemo Attacking

Easy
ArraySimulationArraySimulation
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Approaches

Brute ForceOptimal
Complexity Comparison
Brute ForceOptimal Solution
Time
O(n²)
O(n)
Space
O(n)
O(1)
💡

Intuition

Time O(n)Space O(1)

The optimal approach leverages the fact that we can track the end of the poison effect without needing to store every second. We only need to check if the next attack overlaps with the current poison duration.

⚙️

Algorithm

4 steps
  1. 1Step 1: Initialize a variable to track total poisoned time and another to track the end of the current poison effect.
  2. 2Step 2: Iterate through the timeSeries. For each attack, check if it overlaps with the current poison effect.
  3. 3Step 3: If it overlaps, only add the additional poisoned time. If it doesn't overlap, add the full duration.
  4. 4Step 4: Update the end of the poison effect after each attack.
solution.py12 lines
1# Full working Python code
2
3def totalPoisonedTime(timeSeries, duration):
4    total_time = 0
5    poison_end = 0
6    for attack_time in timeSeries:
7        if attack_time < poison_end:
8            total_time += attack_time + duration - poison_end
9        else:
10            total_time += duration
11        poison_end = attack_time + duration
12    return total_time

Complexity note: This complexity is linear because we only make a single pass through the timeSeries array, performing constant-time operations for each attack.

  • 1Understanding the overlap of poison durations is crucial for optimizing the solution.
  • 2Using a set to track unique seconds can be inefficient; instead, track the total time directly.

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