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Concept
▸1left ← 02right ← n - 13while left < right:4 inspect arr[left] and arr[right]5 decide: move left++ or right--6 (occasionally both)7stop when left ≥ right
state
- n7
Your free access ends in 7 days — and you haven’t tried it yet. Watch one algorithm run, start to finish. It takes about two minutes.
Try one problem▸1left ← 02right ← n - 13while left < right:4 inspect arr[left] and arr[right]5 decide: move left++ or right--6 (occasionally both)7stop when left ≥ right
line 1A two-pointer walk uses just two indices. Most often: one at the start, one at the end.