
Dynamic Unit Forcing Chains 

A Dynamic Unit Forcing Chain is a Unit Forcing Chain that uses Dynamic Forcing Chains instead of Forcing Chains. Basically, if all the candidates in a unit cause the elimination of a candidate through dynamic forcing chains, then that candidate can be eliminated.
Consider the generated example on this page. The unit in question is the 3's in the second column.
The top 3 is weakly connected to the 5 in the same cell, which is strongly connected to the 5 below (in the same cell as the other 3), which is weakly connected to the 5 in blue.
The bottom 3 is weakly connected to the 5 in the same cell, which strongly connected to the 5 above (in the same cell as the other 3), which is weakly connected to the 5 to the right, which is strongly connected to the 5 down below, which is weakly connected to the 5 over to the right.
The bottom 3 is also weakly connected to the pair of 3's in the same box, which are strongly connected to the 3 above, which is weakly connected to the 3 over to the right, which is strongly connected to the 3 below, which is weakly connected to the 5 in the same cell, which is strongly connected to second 5 above (since we've already eliminated the other 5 in the same box from the previous paragraph), which is weakly connected to the 5 in blue.
Thus, no matter where we put the 3 in the second column, we can eliminate the 5 highlighted in blue.
Sudoku Snake gives Dynamic Unit Forcing Chains a skill value of 14000.






