Interactive DSA and system design

Learn complex engineering ideas by watching them move.

20stepsO(n)averageO(1)space

Techniques lab

Sliding Window Max Subarray Sum

Step 1 / 20

Comparing Pivot / Mid Swapping Sorted / Found Active Range

Animation speed

Space play / pause←→ stepR reset

Current operation

Start

Find the maximum sum of any 3 consecutive elements. The window slides from left to right, adding one element and removing one each step.

Algorithm state

3Window Size—Window Sum—Max Sum

Try your own input

Use 3-12 positive numbers separated by commas.

Complexity notes

O(n)averageO(n)worstO(1)spaceN/Astable

Synced code trace

function slidingWindow(arr, k) {  let windowSum = sum(arr[0..k-1]);  let maxSum = windowSum;  for (let i = k; i < arr.length; i++) {    windowSum += arr[i] - arr[i - k];    maxSum = Math.max(maxSum, windowSum);  }  return maxSum;}

Interactive Notes

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