What is the time complexity of Minimum Number of Food Buckets to Feed the Hamsters?

The optimal solution for Minimum Number of Food Buckets to Feed the Hamsters runs in O(n) time and uses O(1) space. The complexity is O(n) because we make a single pass through the string, checking and placing buckets as needed.

What is the brute force solution for Minimum Number of Food Buckets to Feed the Hamsters?

The brute force approach for Minimum Number of Food Buckets to Feed the Hamsters is Brute Force, with O(n²) time complexity and O(1) space complexity. The brute force approach checks every possible placement of food buckets to see if all hamsters can be fed. This method is straightforward but inefficient, as it may require checking many combinations. The optimal Optimal Solution approach improves this to O(n).

What algorithm or data structure is used to solve Minimum Number of Food Buckets to Feed the Hamsters?

Minimum Number of Food Buckets to Feed the Hamsters uses the following concepts: String, Dynamic Programming, Greedy. The recommended patterns to study are: Greedy, Array.

What are the interview tips for Minimum Number of Food Buckets to Feed the Hamsters?

Always clarify the problem constraints and edge cases. Think about greedy strategies for optimization problems. Dry run your solution with sample inputs to validate your logic.

What are common mistakes when solving Minimum Number of Food Buckets to Feed the Hamsters?

Not checking both sides of a hamster before placing a bucket. Assuming all empty spaces can be used without considering hamster positions.

#2086

Minimum Number of Food Buckets to Feed the Hamsters

Medium

StringDynamic ProgrammingGreedyGreedyArray

LeetCode ↗

Approaches

Brute ForceOptimal

Complexity Comparison

	Brute Force	Optimal Solution★
Time	O(n²)	O(n)
Space	O(1)	O(1)

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Intuition

Time O(n)Space O(1)

The optimal approach uses a greedy strategy to place food buckets efficiently. By scanning the string and placing buckets strategically, we minimize the number of buckets needed while ensuring all hamsters are fed.

⚙️

Algorithm

4 steps

1Step 1: Initialize a counter for food buckets and iterate through the string.
2Step 2: When a hamster is found, check the adjacent indices for empty spaces.
3Step 3: Place a food bucket in the optimal position (preferably to the right) to cover the current and next hamster if possible.
4Step 4: Continue until all hamsters are processed or determine if feeding is impossible.

solution.py17 lines

1def minFoodBuckets(hamsters):
2    n = len(hamsters)
3    buckets = 0
4    i = 0
5    while i < n:
6        if hamsters[i] == 'H':
7            if i + 1 < n and hamsters[i + 1] == '.':
8                buckets += 1
9                i += 2  # Skip next index as it's covered
10            elif i - 1 >= 0 and hamsters[i - 1] == '.':
11                buckets += 1
12                i += 1  # Move to next hamster
13            else:
14                return -1
15        else:
16            i += 1
17    return buckets

ℹ

Complexity note: The complexity is O(n) because we make a single pass through the string, checking and placing buckets as needed.

1Hamsters must have adjacent empty spaces to be fed; otherwise, it's impossible.
2Placing buckets optimally (preferably to the right) minimizes the total number needed.

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