Longest substring without repeat

Sliding Window · submitted yesterday

PASSED

Attempts

Time

22 min

Tutor turns

Communication

66/100

Tutor conversation

4 turns

What changes as the window slides one step right?
10:22
One element leaves on the left, one enters on the right.
10:23
Exactly. So what's the cheapest update?
10:23
Subtract leaving, add entering. O(1) per step.
10:24

AI assessment of the conversation

Conversation signals are mixed — review the transcript for context.

Character rubric

Soft-skill signals inferred from the conversation pattern, attempts and pace.

Grit60
Curiosity61
Initiative74
Speed64
Resilience64
Communication66

Academic rubric · this submission

Problem decomposition76
Algorithmic thinking74
Code quality80
Debugging discipline68
Communication with tutor66

Code submission

def max_window_sum(nums, k):
    if k > len(nums): return 0
    window = sum(nums[:k])
    best = window
    for i in range(k, len(nums)):
        window += nums[i] - nums[i - k]
        best = max(best, window)
    return best