42
0
17
1
88
2
33
3
71
4
9
5
56
6
25
7
64
8
12
9
AlgoPlus//sorting / radix sort
Read the theory

Radix Sort · Digit by Digit

Stable counting passes from least to most significant digit.

Stability
Stable
In-Place
No
Space Complexity
O(n+k)
Avg Time
O(nk)
Size10
Legend
Comparing
Swapping / moving
Tracked (min / key)
Pivot
Sorted / found
Out of focus
AI Tutor Workspace
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In a nutshell
Radix sort orders numbers one digit at a time, starting from the rightmost (least-significant) digit and working left. Each pass is a stable bucketing by a single digit, which keeps the order from previous passes intact. After processing the most-significant digit the whole list is sorted — all without ever comparing two numbers directly.
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Sort by one digit at a time, starting from the least-significant, using a stable count on each pass. Ties keep their order, so earlier passes survive and after the last digit everything is sorted.
Key terms
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Read the full theory, intuition & complexity for Radix Sort · Digit by Digit.