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Pattern 07 of 08 · dp-1d

1D Dynamic Programming

Decompose optimization problems into overlapping subproblems with optimal substructure, caching intermediate transition states in linear memory.

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Backtracking & Decision Trees
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Pattern InvariantTwo Pointers

Converging search on sorted array: Target Sum = 26

Step 1 of 3
L
2
[0]
7
[1]
11
[2]
15
[3]
19
[4]
R
23
[5]
nums[0] (2)+nums[5] (23)=25<Target (26)

Sum 25 < target (26). Since array is sorted, we MUST increase left pointer (L: 0 to 1) to seek a larger sum.

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