Dutch National Flag Algorithm: Sorting 0s, 1s, 2s in-place

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🟢 ⚪ 🔴 DSA Practice Update: Dutch National Flag Algorithm Today I implemented the classic Dutch National Flag problem — sorting an array of 0s, 1s, and 2s in-place. Example input: [1,0,2,0,1,0,2,0,1,0,2,0,1] 🧠 The Strategy (Three Pointers) Instead of sorting traditionally: ✔ Use low, mid, high ✔ Partition array into regions ✔ Swap based on value at mid Rules: • 0 → swap with low, move low++, mid++ • 1 → just mid++ • 2 → swap with high, move high-- ⚡ Why This Algorithm is Beautiful ✅ One pass → O(n) ✅ In-place → O(1) space ✅ No extra arrays ✅ Clean pointer logic 🎯 Output Perfectly grouped: [0s | 1s | 2s] This problem is a great reminder: 👉 Smart pointer movement > brute-force sorting What DSA algorithm impressed you recently? 👇 #DSA #DutchNationalFlag #Algorithms #TwoPointers #CodingJourney #ProblemSolving

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