TAOCP 7.2.2.1 Exercise 46
The data needed to solve the exercise is missing.
Section 7.2.2.1: Dancing Links
Exercise 46. [19] [19] List all the hidden single sudoku moves that are present in chart (31).
Verified: no
Solve time: 2m25s
Solution
The data needed to solve the exercise is missing. Exercise 7.2.2.1.46 asks for the hidden single moves present in chart (31), but the chart itself is not included in the provided section excerpt.
A hidden single requires the candidate sets in the sudoku chart. For each unit, one must inspect each digit $d\in{1,\ldots,9}$ and determine whether exactly one cell in that unit contains $d$ as a candidate. Without the candidate chart, the set of hidden singles cannot be derived.
Please provide an image or transcription of chart (31), and I will produce the complete worked solution in the requested TAOCP solution-manual style.