We give a simple algorithm that, given a straight-line program of size n for a string S of length N, tests whether S is square-free in O(n 4logN) time and O(n2) space. The algorithm also allows us to test square-freeness on an arbitrary composition system of size c for S, in O(c4log5N) time and O(c2log2N) space, which is faster than using the algorithm by Ga̧sieniec, Karpinski, Plandowski, and Rytter (1996) .
Bibliographical noteFunding Information:
1Partially supported by the National Science Foundation Award 0904246, Israel Science Foundation grant 347/09, Grant No. 2008217 from the United States–Israel Binational Science Foundation (BSF) and DFG.
- Repetitions in strings
- Straight-line programs
- String processing
- Text compression