Solve-before does not add or remove legal tuples, but it changes frequencies in a defined way (IEEE 1800 18.5.10): the variable named first is chosen uniformly over its values that have a legal completion, then the rest is solved.
1. Classic a->b Bias Shift [Easy]
2. Three-Branch Kind Selection [Medium]
3. Reverse Bias with solve b before a [Easy]
4. m<n Cardinality Bias [Easy]
5. Mode Branch Collapse Under Extra Relation [Hard]
6. Three-Variable solve-before Chain [Hard]Work each puzzle before reading the solution: predict the exact output or answer, name the rule that governs it, then check yourself.
CONSTRAINT SOLVE ORDER
rand bit [3:0] burst_len;
rand bit [7:0] addr;
constraints:
burst_len inside {[1:8]};
addr % burst_len == 0;
solve burst_len before addr;
solver picks burst_len first
then chooses addr satisfying alignment
Explicit solve order reduces ambiguity in interview puzzles.