PREVIOUS YEAR SOLVED PAPERS - GATE 2019
| Productions rule | Semantic action |
| D → TL | X1 .type = X2 .type |
| T → int | T.type = int |
| T → float | T.type = float |
| L → L1 , id | X3 .type = X4 .type add Type(id.entry, X5 .type) |
| L → id | addType(id.entry, X6 .type) |
Which one of the following are the appropriate choices for 𝑋1, 𝑋2, 𝑋3 and 𝑋4?
- Option : A
- Explanation : SDT for inserting type information in the symbol table D → TL {L.idtype = T.stype} T → int {T.stype = int} T → float {T.stype = float} L → L1, id {L1.itype = L.itype} addtype(id.entry, L.itype) L → id addtype(id.entry, L.itype)
- Option : C
- Explanation : If no two edges of G have same weight surely G will have unique spanning tree is true. So I is true Also if, for every cut of G, there is a unique minimum weight edge crossing the cut then G will have unique spanning tree is also true. So II is true [Note: The converse of II is not true, but that is not relevant to this question] So both I and II are true. Option (C) is correct.
