AI_CA_1_AIRISH.R.PILLAI_B463

Name :- Airish Pillai

Roll no :-B463

subject :- Artificial Intelligence 

Prn no :- 2246491245509

Que :- Give a complete problem formulation for each of the following. Choose a formulation that is precise enough to be implemented.

c. You have a program that outputs the message “illegal input record” when fed a certain file of input records. You know that processing of each record is 

independent of the other records. You want to discover what record is illegal.

 Ans :- To precisely formulate the problem where you need to discover the illegal input record in a file, you can frame it as follows:

Problem Formulation Given: Input: A file containing a series of input records. Let the total number of records in the file be denoted as nn. A program that processes these records one by one and outputs the message "illegal input record" if a record is found to be illegal. Program: The program, when fed a record, will process the record and output either: "illegal input record" if the record is determined to be illegal, or "no error" if the record is valid. Assumptions: Each record is independent of the others, meaning that the illegal record can be isolated without dependencies on the other records. Only one record is illegal, though the formulation can be adapted if multiple illegal records are possible. Objective:-

Your objective is to identify the illegal input record in the file using the program.

Approach:-

Strategy: To efficiently find the illegal record, perform a systematic search through the input file, leveraging the program to check the legality of each record.

Steps:-

Input File: Assume the file is composed of nn records, indexed from 11 to nn. Process Each Record: For each record rir_i (where ii is the index from 1 to nn): Feed rir_i into the program. If the program outputs "illegal input record", record rir_i is the illegal record. If the program outputs "no error", move on to the next record. Stop when: The program identifies the illegal record, and output this record. Pseudo-code: def find_illegal_record(file): records = read_file(file) # Reads the file into a list of records for i, record in enumerate(records): if is_illegal(record): return i # Return the index of the illegal record return None # If no illegal record is found, return None def is_illegal(record): # Simulate the program that determines if the record is illegal if process(record) == "illegal input record": return True return False 

Where:-

read_file(file) reads the input file and returns a list of records. process(record) is the function that simulates the external program that processes each record. Time Complexity: The time complexity of this approach is O(n)O(n), as you may have to check all nn records in the worst case. Edge Cases: If the file contains no records, the output should be None. If the illegal record is the first or last record, the program should still find it efficiently. 

This formulation is simple and precise enough to implement while ensuring efficiency and clarity in identifying the illegal record.