What the board asks
We went through the ISC board papers, question by question, and matched each question to a topic. Here is what was asked, how often, and what was never asked.
Computer Science: 180 topics in the 2027 syllabus, across 10 units. The board has asked 117 of them at least once. 63 were never asked in the papers we checked.
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CS4 Types, Variables, Expressions and Statements
All the topics in Computer Science: Types, Variables, Expressions and Statements
Asked topics first, the most asked at the top. Tap a topic to see what to write, the result, the years, and the real board questions.
22 topics shown
| # | Topic | Type | Marks | Times asked | Last asked | Status |
|---|---|---|---|---|---|---|
| 1 | Output of switch case with and without breakDry-run a switch for a given value, follow fall-through when break is missing, apply default, and write the exact output. | Dry run / output | 1 | 1 paper | 2025 | Asked |
| 2 | Effect of break and continue in loops and switchState what break and continue do in a loop and what break does in a switch, judge assertion-reason statements about them, and give the output of a short loop using them. | Give reason | 1 | 1 paper | 2025 | Asked |
| 3 | Output of a loop: dry run with a value tableDry-run a for, while or do-while loop (including nested loops and digit loops) with a table of variable values per iteration, and write the returned value or exact output. | Dry run / output | 2 | 1 paper | 2023 | Asked |
| 4 | State what a given loop method doesRead a short loop-based method, test it on two or three values, and name in one line what it computes or checks. | Give reason | 1 | 1 paper | 2023 | Asked |
| 5 | Wrapper classes, autoboxing and unboxingDefine a wrapper class, pair each primitive with its wrapper, give two examples, and define autoboxing and unboxing with a one-line example each. | Statement | 2 | 1 paper | 2018 | Asked |
| 6 | The eight primitive types, sizes and defaultsList byte, short, int, long, float, double, char and boolean with size in bytes, default value of a data member, and a literal of each. | Statement | 1 | never | Never asked | |
| 7 | Output of wrapper class method callsWrite the exact value and type returned by common wrapper methods such as Integer.parseInt, Integer.toString, Double.parseDouble, Character.isDigit, isLetter, isUpperCase, toUpperCase, toLowerCase. | Dry run / output | 1 | never | Never asked | |
| 8 | Class as a user-defined typeExplain that a class is the type of its objects and the way to make a user-defined (composite) type, and contrast it with a primitive type in one example. | Statement | 1 | never | Never asked | |
| 9 | Implicit type coercion versus explicit castingDistinguish automatic widening conversion from explicit (narrowing) casting with one Java example each, and state the widening order. | Comparison | 2 | never | Never asked | |
| 10 | Output of mixed-type and cast expressionsEvaluate short expressions mixing int, double and char, with and without casts, and write the exact value and its type as Java would print it. | Dry run / output | 1 | never | Never asked | |
| 11 | Variables, named constants and finalDefine a variable and a named constant, declare a constant with final, and state what happens if code tries to change it. | Statement | 1 | never | Never asked | |
| 12 | Left-hand side versus right-hand side of assignmentExplain that the right side is an expression evaluated to a value and the left side must name a storage location, and judge whether given statements are valid assignments. | Give reason | 1 | never | Never asked | |
| 13 | Evaluate an expression by precedence and associativityEvaluate a given arithmetic or mixed expression step by step, applying precedence and left or right associativity, and give the final value. | Sum | 2 | never | Never asked | |
| 14 | Output with prefix and postfix increment and decrementTrack the variable values through an expression or statements using ++ and -- in prefix and postfix form, and write the final values and the printed output. | Dry run / output | 1 | never | Never asked | |
| 15 | Relational and logical expressions with short-circuit evaluationEvaluate expressions using relational operators, &&, || and !, noting where the right operand is not evaluated, and give the boolean result and any side effects. | Dry run / output | 1 | never | Never asked | |
| 16 | Write a Java expression for a formulaRewrite a given mathematical expression as a correct Java expression using Math methods and brackets where needed. | Sum | 1 | never | Never asked | |
| 17 | Output of if, if-else and if-else-if codeDry-run nested or chained if statements for given values, decide which branch runs (including dangling else), and write the exact output. | Dry run / output | 1 | never | Never asked | |
| 18 | Ternary operator to and from if-elseRewrite a given if-else as a single statement using ?: (or the reverse), and evaluate a nested ternary for given values. | Sum | 1 | never | Never asked | |
| 19 | Entry-controlled versus exit-controlled loops; convert one loop to anotherGive the difference between while/for and do-while with an example, and rewrite a given loop in another form so that it does the same work. | Comparison | 2 | never | Never asked | |
| 20 | Fill the blanks in a short loop-based methodRead a method with numbered blanks, work out from its purpose the missing condition, update or expression for each blank, and write each answer against its number. | Program | 3 | never | Never asked | |
| 21 | Scope of local, instance and class variablesFor a given class, state the scope and lifetime of each variable (local, parameter, loop variable, instance, static), say which one a name refers to when a local hides a data member, and how this resolves it. | Give reason | 2 | never | Never asked | |
| 22 | Find and correct errors in a short code fragmentLocate each syntax or type error (missing cast, wrong type, variable out of scope, = for ==, missing break) in a short fragment and write the corrected line. | Program | 2 | never | Never asked |
This list was made from the 2027 syllabus and checked with 9 board papers, including the 2027 specimen paper. It is not yet checked with the textbook.
The 10 topics Computer Science papers ask most
Counted on the board papers from 2018 to the 2027 specimen paper, which every unit has been checked against.
- 1.Principle of duality: state it and write the dualCS1 Boolean Algebra · asked 8 times since 2018
- 2.Complement of an expression using De Morgan's theoremCS1 Boolean Algebra · asked 8 times since 2018
- 3.Word problem to truth table and SOP or POSCS1 Boolean Algebra · asked 8 times since 2018
- 4.K-map reduction of a four-variable POS expressionCS1 Boolean Algebra · asked 8 times since 2018
- 5.Pre-order, in-order and post-order traversalCS9 Data Structures · asked 8 times since 2018
- 6.K-map reduction of a four-variable SOP expressionCS1 Boolean Algebra · asked 7 times since 2018
- 7.Read a tree: leaves, internal nodes, parent, siblings, degreeCS9 Data Structures · asked 7 times since 2018
- 8.Truth table to classify tautology, contradiction or contingencyCS1 Boolean Algebra · asked 6 times since 2018
- 9.Convert between cardinal and canonical formsCS1 Boolean Algebra · asked 6 times since 2018
- 10.Address of an element, row major and column majorCS6 Arrays and Strings · asked 6 times since 2018