ISC 2017 Computer Science Practical Question Paper for Class 12

About this paper

This is ISC Class 12 Computer Science Paper 2 (Practical), code 868B, from the 2017 examination. It carries 30 marks and runs for three hours plus fifteen minutes of reading time, with 90 minutes for planning and 90 minutes at the computer. Candidates attempt any one of three Java problems: packing boxes into cartons of 48, 24, 12 and 6, scoring a five-question quiz, or encrypting text with the ROT13 Caesar cipher. Twenty marks cover the algorithm, program, documentation, printout, test run and viva-voce. The programming file carries 5 marks from the teacher and 5 from the Visiting Examiner. This copy has the questions only.

Exam

ISC Class 12

Subject

Computer Practical

Year

2017

Paper code

868B

Maximum marks

30

Time allowed

3 hours + 15 min reading

Questions

3

Pages

5

Answers included

No, questions only

Paper pattern

• Selected problem

  20 marks

  Attempt any one of three Java problems: algorithm (3), program (5), documentation (2), printout (2), test run (5) and viva-voce (3)

• Practical file

  10 marks

  Programming assignments done during the year, assessed by the teacher (5) and by the Visiting Examiner (5)

Topics covered

• Carton packing
• Input validation
• Two-dimensional arrays
• Quiz scoring
• Caesar cipher and ROT13
• Java programming and the practical file

Questions from this paper

1. Cartons hold 6, 12, 24 or 48 boxes. Accept the number of boxes N, which is at most 1000, and display the cartons used in descending order of capacity. If fewer than 6 boxes remain, use one extra carton of capacity 6. For N = 726 the breakup is 48 × 15 = 720 and 6 × 1 = 6.
2. A quiz has five questions, each marked A, B, C or D, with one mark for a correct answer. Accept N participants, where N is greater than 3 and less than 11, store the answers in an N × 5 array, score them against a key of five answers, and display the scores and the participant or participants with the highest score.
3. ROT13 replaces each letter by the letter 13 places later in the alphabet and leaves every other character unchanged. Accept plain text whose length L is greater than 3 and less than 100, and print the cipher text.
4. Write an algorithm for the chosen problem and a Java program that follows it and is logically and syntactically correct.
5. Document the program with mnemonic names and comments, identifying the data type and meaning of each variable, and produce a printout of the test run in the format given.