String Sorting: LSD Radix Sort

String Sorting: LSD Radix Sort

Sort strings stably from the rightmost character to the leftmost character using buckets.

How to use

• Enter comma-separated strings (up to 12 strings of at most 10 characters) and press Load Data.
• Step Forward performs one pass: every string goes into the bucket of its character at the current position, then the buckets are concatenated in character order. Auto Run performs the remaining passes; Reset reloads the input.
• The highlighted column is the position used in the last pass; green columns have already been processed.

Different lengths

If strings have different lengths, shorter strings are internally right-padded with blank characters (shown as ·) so that every position can be processed. The blank sorts before every other character, so a string comes before its own extensions (for example "be" before "bed"), which is the lexicographic order.

Why it works

Each pass is a stable distribution: strings with equal characters at the current position keep the order produced by the earlier passes. After the pass on position 0, the strings are sorted by all positions.

Complexity