Question 1
Printed graph sheets were provided on time.
Printed graph sheets were provided late.
Printed graph sheets were not provided.
I used the graph sheets.
I did not use graph sheets.

The IIT Madras BS AI: Search Methods for Problem Solving (AI Search Methods) End Term paper sat on 21 Dec 2025, in the September 2025 term: 34 questions for 34 marks in 180 minutes. Every question is below with its answer. Take it as a timed mock test to be marked, or read it through first.
Printed graph sheets were provided on time.
Printed graph sheets were provided late.
Printed graph sheets were not provided.
I used the graph sheets.
I did not use graph sheets.
Correct answers
Printed graph sheets were provided on time.
I used the graph sheets.
SEARCH The figure shows a map on a uniform grid where each tile is 1x1 in size. The start node is S and the goal node is G. The MoveGen function returns nodes in alphabetical order. Use Manhattan Distance as the heuristic function. Tie-breaker: If several nodes have the same cost, use node labels to break the tie.
Based on the above data, answer the given subquestions.
What is the path found by the Best First Search algorithm? Enter the path as a comma separated list of node labels. NO SPACES, TABS, DOTS, BRACKETS OR EXTRANEOUS CHARACTERS. Answer format: S,X,Y,Z,G Answers Case Sensitive : No
A written answer, not marked automatically.
SEARCH The figure shows a map on a uniform grid where each tile is 1x1 in size. The start node is S and the goal node is G. The MoveGen function returns nodes in alphabetical order. Use Manhattan Distance as the heuristic function. Tie-breaker: If several nodes have the same cost, use node labels to break the tie.
Based on the above data, answer the given subquestions.
Answers Case Sensitive : No
A written answer, not marked automatically.
SEARCH The figure shows a map on a uniform grid where each tile is 1x1 in size. The start node is S and the goal node is G. The MoveGen function returns nodes in alphabetical order. Use Manhattan Distance as the heuristic function. Tie-breaker: If several nodes have the same cost, use node labels to break the tie.
Based on the above data, answer the given subquestions.
What is the path found by Branch-and-Bound search algorithm? Enter the path as a comma separated list of node labels. NO SPACES, TABS, DOTS, BRACKETS OR EXTRANEOUS CHARACTERS. Answer format: S,X,Y,Z,G Answers Case Sensitive : No
A written answer, not marked automatically.
SEARCH The figure shows a map on a uniform grid where each tile is 1x1 in size. The start node is S and the goal node is G. The MoveGen function returns nodes in alphabetical order. Use Manhattan Distance as the heuristic function. Tie-breaker: If several nodes have the same cost, use node labels to break the tie.
Based on the above data, answer the given subquestions.
For the given map, which algorithm finds the shortest path from S to G?
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Correct answer
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SEARCH The figure shows a map on a uniform grid where each tile is 1x1 in size. The start node is S and the goal node is G. The MoveGen function returns nodes in alphabetical order. Use Manhattan Distance as the heuristic function. Tie-breaker: If several nodes have the same cost, use node labels to break the tie.
Based on the above data, answer the given subquestions.
Select the correct statement about the given graph.
Heuristic is admissible.
Heuristic is not admissible.
Heuristic is admissible in some cases and not admissible in other cases.
There is not enough information to determine admissibility.
Correct answer
Heuristic is not admissible.
GAMES: ALPHA-BETA Consider a game tree with the root node as MAX. Alpha-Beta algorithm is in mid-flight currently processing a path from the root to a node labeled N. The snapshot of evals of nodes along the current path is: 2, 14, 4, 10, N. Where evals are restricted to EVEN NUMBERS greater than zero and less than 15. Based on the above data, answer the given subquestions.
Determine the eval of node N that will induce a cutoff to prune its siblings. Enter an even number. NO SPACES, TABS, DOTS, BRACKETS OR EXTRANEOUS CHARACTERS. Answer format: 16
A written answer, not marked automatically.
GAMES: ALPHA-BETA Consider a game tree with the root node as MAX. Alpha-Beta algorithm is in mid-flight currently processing a path from the root to a node labeled N. The snapshot of evals of nodes along the current path is: 2, 14, 4, 10, N. Where evals are restricted to EVEN NUMBERS greater than zero and less than 15. Based on the above data, answer the given subquestions.
What type of cut-off is induced by the eval selected for N?
Alpha Cutoff
Beta Cutoff
Alpha-Beta Cutoff
None of these
Correct answer
Alpha Cutoff
GAMES: SSS STAR The figure shows a game tree with evaluation function values at the horizon nodes. The horizon nodes are labeled from A to D. Use these labels to enter a horizon node or a list of horizon nodes in short answers. Tie-breaker: When several nodes carry the same best cost then select the deepest node, if tie persists then select the leftmost of the deepest nodes to break the tie.
Run SSS* algorithm on the game tree, then answer the sub-questions.
Answers Case Sensitive : No
A written answer, not marked automatically.
GAMES: SSS STAR The figure shows a game tree with evaluation function values at the horizon nodes. The horizon nodes are labeled from A to D. Use these labels to enter a horizon node or a list of horizon nodes in short answers. Tie-breaker: When several nodes carry the same best cost then select the deepest node, if tie persists then select the leftmost of the deepest nodes to break the tie.
Run SSS* algorithm on the game tree, then answer the sub-questions.
Answers Case Sensitive : No
A written answer, not marked automatically.
PROBLEM DECOMPOSITION The figure shows an AND-OR decomposition of problem S into smaller problems. The nodes are uniquely identified by labels (S, A, B, C, …). Each node shows the heuristic estimate of the cost of solving that node. Nodes shown in double lines are primitive nodes and their values are actual costs. A primitive node is added to the graph, with SOLVED status, when its parent is expanded. And therefore, a primitive node is never expanded. The cost of each edge is 2 units. Tie-breaker 1: If several nodes have the same cost then break the tie using node labels. Tie-breaker 2: For AND nodes, select the unsolved branch with the highest cost.
Use AO* algorithm to solve S, then answer the sub-questions.
Answers Case Sensitive : No
A written answer, not marked automatically.
PROBLEM DECOMPOSITION The figure shows an AND-OR decomposition of problem S into smaller problems. The nodes are uniquely identified by labels (S, A, B, C, …). Each node shows the heuristic estimate of the cost of solving that node. Nodes shown in double lines are primitive nodes and their values are actual costs. A primitive node is added to the graph, with SOLVED status, when its parent is expanded. And therefore, a primitive node is never expanded. The cost of each edge is 2 units. Tie-breaker 1: If several nodes have the same cost then break the tie using node labels. Tie-breaker 2: For AND nodes, select the unsolved branch with the highest cost.
Use AO* algorithm to solve S, then answer the sub-questions.
Answers Case Sensitive : No
A written answer, not marked automatically.
PROBLEM DECOMPOSITION The figure shows an AND-OR decomposition of problem S into smaller problems. The nodes are uniquely identified by labels (S, A, B, C, …). Each node shows the heuristic estimate of the cost of solving that node. Nodes shown in double lines are primitive nodes and their values are actual costs. A primitive node is added to the graph, with SOLVED status, when its parent is expanded. And therefore, a primitive node is never expanded. The cost of each edge is 2 units. Tie-breaker 1: If several nodes have the same cost then break the tie using node labels. Tie-breaker 2: For AND nodes, select the unsolved branch with the highest cost.
Use AO* algorithm to solve S, then answer the sub-questions.
What can you conclude about the given AND-OR decomposition?
The heuristic is admissible.
The heuristic is inadmissible.
The heuristic is sometimes admissible and sometimes inadmissible.
Correct answer
The heuristic is inadmissible.
RULE BASED EXPERT SYSTEMS A Rete Net for classification of vehicles is shown in the figure. Labels A1, A2, A3, ..., A10, A11, A12, A13, ..., and B1, B2, B3 uniquely identify nodes in the network. When required, use the above label ordering to break ties and to enter short answers.
The Working Memory contains the following WMEs uniquely identified by timestamps (sequence numbers). Assume that WMEs reside in the appropriate Alpha node, and Beta nodes simply point to WMEs in the Alpha nodes.
For each WME identify its location (node label) in the Rete Net, then prepare the conflict set for the first Match-Resolve-Execute cycle, then answer the sub-questions.
Which of the following rule-data tuples occur in the conflict set?
Luxury-Car,104,107
Minivan,103,106
Truck,101,102,105
Minivan,103,106,108
Correct answers
Luxury-Car,104,107
Minivan,103,106
Truck,101,102,105
RULE BASED EXPERT SYSTEMS A Rete Net for classification of vehicles is shown in the figure. Labels A1, A2, A3, ..., A10, A11, A12, A13, ..., and B1, B2, B3 uniquely identify nodes in the network. When required, use the above label ordering to break ties and to enter short answers.
The Working Memory contains the following WMEs uniquely identified by timestamps (sequence numbers). Assume that WMEs reside in the appropriate Alpha node, and Beta nodes simply point to WMEs in the Alpha nodes.
For each WME identify its location (node label) in the Rete Net, then prepare the conflict set for the first Match-Resolve-Execute cycle, then answer the sub-questions.
If the Inference Engine uses Specificity for conflict resolution then which rule-data tuple will fire in the first round?
Luxury-Car,104,107
Minivan,103,106
Truck,101,102,105
Minivan,103,106,108
Correct answer
Truck,101,102,105
RULE BASED EXPERT SYSTEMS A Rete Net for classification of vehicles is shown in the figure. Labels A1, A2, A3, ..., A10, A11, A12, A13, ..., and B1, B2, B3 uniquely identify nodes in the network. When required, use the above label ordering to break ties and to enter short answers.
The Working Memory contains the following WMEs uniquely identified by timestamps (sequence numbers). Assume that WMEs reside in the appropriate Alpha node, and Beta nodes simply point to WMEs in the Alpha nodes.
For each WME identify its location (node label) in the Rete Net, then prepare the conflict set for the first Match-Resolve-Execute cycle, then answer the sub-questions.
If the Inference Engine uses Recency for conflict resolution which rule-data tuple will fire in the first round?
Luxury-Car,104,107
Minivan,103,106
Truck,101,102,105
Minivan,103,106,108
Correct answer
Luxury-Car,104,107
AUTOMATED PLANNING 1 Answer the given subquestions.
Consider actions a and b and two feasible orderings (a then b) and (b then a). Which of the following conditions will produce different outcomes for each ordering?
P is in pre(a) and also in del-effects(b).
P is in add-effects(a) and also in del-effects(b).
None of these.
Correct answer
P is in add-effects(a) and also in del-effects(b).
AUTOMATED PLANNING 1 Answer the given subquestions.
In planning graphs constructed by GraphPlan, actions a and b in layer n are mutex __________ .
if P in pre(a) and Q in pre(b) are mutex
if P is in pre(a), in del-effects(a), in pre(b) and also in del-effects(b)
if P is in pre(a) and also in del-effects(b)
if P is in add-effects(a) and also in del-effects(b)
Correct answers
if P in pre(a) and Q in pre(b) are mutex
if P is in pre(a), in del-effects(a), in pre(b) and also in del-effects(b)
if P is in pre(a) and also in del-effects(b)
if P is in add-effects(a) and also in del-effects(b)
AUTOMATED PLANNING 1 Answer the given subquestions.
In planning graphs constructed by GraphPlan, propositions P and Q in layer n are mutex __________ .
if every action pair (a,b) with P in add-effects(a) and Q in add-effects(b) in layer n is mutex
if at least one action pair (a,b) with P in add-effects(a) and Q in add-effects(b) in layer n is mutex
none of these
Correct answer
if every action pair (a,b) with P in add-effects(a) and Q in add-effects(b) in layer n is mutex
AUTOMATED PLANNING 2 The domain description of a Blocks World with a single one-armed robot is given below.
The GraphPlan algorithm is in mid-flight solving a planning problem, from the planning graph two consecutive propositional layers (layer k and k+1) are presented in the figure. Both proposition layers are fully populated (no missing propositions).
Mutex proposition pairs in layer k are: (on(A,B), holding(A)), (on(A,B), clear(B)), (armEmpty, clear(B)), (armEmpty, holding(A)). Populate the action layer and mutex links, then answer the sub-questions.
What can you conclude about layer k?
Layer k describes the start state of the planning problem.
Layer k cannot describe the start state of the planning problem.
There is insufficient information to comment on layer k.
Correct answer
Layer k cannot describe the start state of the planning problem.
AUTOMATED PLANNING 2 The domain description of a Blocks World with a single one-armed robot is given below.
The GraphPlan algorithm is in mid-flight solving a planning problem, from the planning graph two consecutive propositional layers (layer k and k+1) are presented in the figure. Both proposition layers are fully populated (no missing propositions).
Mutex proposition pairs in layer k are: (on(A,B), holding(A)), (on(A,B), clear(B)), (armEmpty, clear(B)), (armEmpty, holding(A)). Populate the action layer and mutex links, then answer the sub-questions.
Which of the following are applicable actions in layer k+1?
Putdown(A)
Stack(A,B)
Unstack(A,B)
Unstack(B,C)
Correct answers
Putdown(A)
Stack(A,B)
Unstack(A,B)
AUTOMATED PLANNING 2 The domain description of a Blocks World with a single one-armed robot is given below.
The GraphPlan algorithm is in mid-flight solving a planning problem, from the planning graph two consecutive propositional layers (layer k and k+1) are presented in the figure. Both proposition layers are fully populated (no missing propositions).
Mutex proposition pairs in layer k are: (on(A,B), holding(A)), (on(A,B), clear(B)), (armEmpty, clear(B)), (armEmpty, holding(A)). Populate the action layer and mutex links, then answer the sub-questions.
Which of the following are mutex pairs in layer k+1?
Putdown(A) and Stack(A,B)
Stack(A,B) and Unstack(A,B)
nop-3 and nop-4
Correct answers
Putdown(A) and Stack(A,B)
Stack(A,B) and Unstack(A,B)
nop-3 and nop-4
AUTOMATED PLANNING 2 The domain description of a Blocks World with a single one-armed robot is given below.
The GraphPlan algorithm is in mid-flight solving a planning problem, from the planning graph two consecutive propositional layers (layer k and k+1) are presented in the figure. Both proposition layers are fully populated (no missing propositions).
Mutex proposition pairs in layer k are: (on(A,B), holding(A)), (on(A,B), clear(B)), (armEmpty, clear(B)), (armEmpty, holding(A)). Populate the action layer and mutex links, then answer the sub-questions.
armEmpty and clear(B) in layer k+1 are non mutex because __________ .
nop-3 and nop-4 are non mutex
PutDown(A) and nop-4 are non mutex
None of these
Correct answer
PutDown(A) and nop-4 are non mutex
CONSTRAINT SATISFACTION Consider a CSP over 3 variables A, B, C (processed in that order) with domains and constraints as shown below.
Draw the constraint graph and matching-diagram then answer the sub-questions.
Is the given CSP arc consistent?
Yes
No
Cannot be determined
Correct answer
No
CONSTRAINT SATISFACTION Consider a CSP over 3 variables A, B, C (processed in that order) with domains and constraints as shown below.
Draw the constraint graph and matching-diagram then answer the sub-questions.
If the given CSP is not already arc consistent, make it arc consistent, then check if it is path consistent.
It is path consistent.
It is not path consistent.
Path consistency does not apply because the constraint graph is cyclic.
Correct answer
It is path consistent.
CONSTRAINT SATISFACTION Consider a CSP over 3 variables A, B, C (processed in that order) with domains and constraints as shown below.
Draw the constraint graph and matching-diagram then answer the sub-questions.
Does the given CSP have a solution? Enter the solution for the variables A,B,C as a comma separated list. Enter NIL if there is no solution. NO SPACES, TABS, DOTS, BRACKETS OR EXTRANEOUS CHARACTERS. Answer format: 1,2,3 Answers Case Sensitive : No
A written answer, not marked automatically.
SEARCH The figure shows a map on a uniform grid where each tile is 1x1 in size. The start node is S and the goal node is G. The MoveGen function returns nodes in alphabetical order. Use Manhattan Distance as the heuristic function. Tie-breaker: If several nodes have the same cost, use node labels to break the tie.
Based on the above data, answer the given subquestions.
A written answer, not marked automatically.
GAMES: ALPHA-BETA Consider a game tree with the root node as MAX. Alpha-Beta algorithm is in mid-flight currently processing a path from the root to a node labeled N. The snapshot of evals of nodes along the current path is: 2, 14, 4, 10, N. Where evals are restricted to EVEN NUMBERS greater than zero and less than 15. Based on the above data, answer the given subquestions.
A written answer, not marked automatically.
GAMES: SSS STAR The figure shows a game tree with evaluation function values at the horizon nodes. The horizon nodes are labeled from A to D. Use these labels to enter a horizon node or a list of horizon nodes in short answers. Tie-breaker: When several nodes carry the same best cost then select the deepest node, if tie persists then select the leftmost of the deepest nodes to break the tie.
Run SSS* algorithm on the game tree, then answer the sub-questions.
A written answer, not marked automatically.
PROBLEM DECOMPOSITION The figure shows an AND-OR decomposition of problem S into smaller problems. The nodes are uniquely identified by labels (S, A, B, C, …). Each node shows the heuristic estimate of the cost of solving that node. Nodes shown in double lines are primitive nodes and their values are actual costs. A primitive node is added to the graph, with SOLVED status, when its parent is expanded. And therefore, a primitive node is never expanded. The cost of each edge is 2 units. Tie-breaker 1: If several nodes have the same cost then break the tie using node labels. Tie-breaker 2: For AND nodes, select the unsolved branch with the highest cost.
Use AO* algorithm to solve S, then answer the sub-questions.
A written answer, not marked automatically.
RULE BASED EXPERT SYSTEMS A Rete Net for classification of vehicles is shown in the figure. Labels A1, A2, A3, ..., A10, A11, A12, A13, ..., and B1, B2, B3 uniquely identify nodes in the network. When required, use the above label ordering to break ties and to enter short answers.
The Working Memory contains the following WMEs uniquely identified by timestamps (sequence numbers). Assume that WMEs reside in the appropriate Alpha node, and Beta nodes simply point to WMEs in the Alpha nodes.
For each WME identify its location (node label) in the Rete Net, then prepare the conflict set for the first Match-Resolve-Execute cycle, then answer the sub-questions.
A written answer, not marked automatically.
AUTOMATED PLANNING 1 Answer the given subquestions.
A written answer, not marked automatically.
AUTOMATED PLANNING 2 The domain description of a Blocks World with a single one-armed robot is given below.
The GraphPlan algorithm is in mid-flight solving a planning problem, from the planning graph two consecutive propositional layers (layer k and k+1) are presented in the figure. Both proposition layers are fully populated (no missing propositions).
Mutex proposition pairs in layer k are: (on(A,B), holding(A)), (on(A,B), clear(B)), (armEmpty, clear(B)), (armEmpty, holding(A)). Populate the action layer and mutex links, then answer the sub-questions.
A written answer, not marked automatically.
CONSTRAINT SATISFACTION Consider a CSP over 3 variables A, B, C (processed in that order) with domains and constraints as shown below.
Draw the constraint graph and matching-diagram then answer the sub-questions.
A written answer, not marked automatically.