Swaps [mp]

Micro pattern¶

Description¶

Exchange two positions or semantic states in constant time to restore an invariant.

Problems¶

Comparison sorting¶

Exchange elements to place them in appropriate regions.

• Bubble sort (DSA)
• Quick sort (DSA)
• Heap sort (DSA)
• Selection sort (DSA)

Reversal and rotation¶

Swap symmetric positions while moving inward.

• 48. Rotate Image (Top Easy)
• 189. Rotate Array (Top Easy)
• 344. Reverse String (Top Easy)

In-place partitioning¶

Swap values into their target regions or natural positions.

• 75. Sort Colors (Top Medium)
• 41. First Missing Positive (Top Hard)
• 283. Move Zeroes (Top Easy)

Permutation generation¶

Swap remaining values into positions and undo swaps after exploration.

• 46. Permutations (Top Medium)
• 384. Shuffle an Array (Top Easy)

Constant-time unordered deletion¶

Replace a removed array slot with its final element.

• 380. Insert Delete GetRandom O(1) (Top Medium)

Swap semantic extremes¶

Exchange minimum and maximum summaries when their roles reverse.

• 152. Maximum Product Subarray (Top Hard)