ICSE Class 10 Computer Applications 2026 Prediction Paper with Solutions

Answer: (a) 3

a++ uses a=8 (post-increment), a becomes 9. ++b makes b=4. c = 8 + 4 - 9 = 3.

Answer: (b) — Standard syntax for 2D array creation in Java.

Answer: (a) — Both true. R correctly explains why compareTo() returns an int (Unicode difference).

Answer: (a) PREION

substring(0,3) = "PRE" (index 0,1,2). substring(7) = "ION" (index 7 to end). Concatenated = "PREION".

Answer: (b) — Math.round(double) returns long. ceil and floor return double. abs(int) returns int.

Answer: (a) YES YES NO

Line 1: 5>3 AND 5<10 = true. Line 2: 5>3 = true (short-circuit). Line 3: NOT(true) = false.

Answer: (d) false — boolean arrays default to false.

Answer: (b) — Constructors cannot have a return type. int Test() is treated as a regular method, not a constructor.

Answer: (b) true z — isUpperCase('Z') returns true. toLowerCase('Z') returns 'z'.

Answer: (b) — Autoboxing: primitive int 5 is automatically wrapped into Integer object.

Answer: (c) 2 — The loop finds the minimum element. Minimum of {3,7,2,9,5} = 2.

Answer: (a) — Both true. R correctly explains why private methods can't be accessed externally.

Answer: (a) 7 — 'J'(74) - 'C'(67) = 7. First characters differ, returns the difference.

Answer: (b) — 3 constructors with different parameter lists = Constructor Overloading (a form of polymorphism).

Answer: (a) 18 — Multiples of 3 from 1 to 10: 3 + 6 + 9 = 18.

Answer: (a) — Return type char, parameters String and int.

Answer: (b) 3 — Vowels in "COMPUTER": O, U, E = 3.

Answer: (b) TEN TWENTY — case 10 matches, prints "TEN ". No break → falls through to case 20, prints "TWENTY ". Break exits switch.

Answer: (a) 9.0 — pow(2,3)=8.0, sqrt(16)=4.0, abs(-3)=3. Result: 8+4-3 = 9.0.

Answer: (c) — Recursion requires self-call with modified argument converging to a base case.

Output:

15
true
2026
2 6

length()=15, startsWith("Exam")=true, substring(11)="2026", first 'a' at index 2, last 'a' at index 6.

Output:

result = 7
a = 4 b = 4

++a → a=4. b-- uses b=5, then b=4. Precedence: 5*7=35, 35%4=3. result = 4+3 = 7.

(a) (4.0 / 3) * Math.PI * Math.pow(r, 3)

(b) Math.sqrt(Math.pow(x2 - x1, 2) + Math.pow(y2 - y1, 2))

Output: x = 21

i=1: x=1+1=2. i=2: x=2+1+2=5. i=3: x=5+1+2+3=11. i=4: x=11+1+2+3+4=21.

(a) length() is a method (with parentheses): s.length(). length is a property (no parentheses): arr.length.

(b) Call by value: copy of value is passed; changes don't affect the original (used for primitives). Call by reference: reference is passed; changes affect the original object (used for objects/arrays).

Errors:

1. Comma , should be semicolon ; in for-loop: i <= n; i++
2. Missing semicolon after System.out.println(i * i)
3. Two methods with identical signatures void show(int n) — not valid overloading. Change one parameter type.

if(grade == 'A')
    System.out.println("Excellent");
else if(grade == 'B')
    System.out.println("Good");
else if(grade == 'C')
    System.out.println("Average");
else
    System.out.println("Invalid");

(a) Character.isLetterOrDigit() (b) replace() (c) Double.parseDouble() (d) Math.abs()

Output: T-H-G-I-R-B

Reverses "BRIGHT" with dashes between each character.

int n = 1234, rev = 0;
do
{
    rev = rev * 10 + n % 10;
    n /= 10;
} while(n > 0);
System.out.println(rev);  // Output: 4321

import java.util.Scanner;

class ElectricBill
{
    String name;
    int units;
    double bill;

    ElectricBill(String n, int u)
    {
        name = n;
        units = u;
        bill = 0.0;
    }

    void calculateBill()
    {
        if(units <= 100)
            bill = units * 2.00;
        else if(units <= 300)
            bill = 100 * 2.00 + (units - 100) * 4.50;
        else if(units <= 500)
            bill = 100 * 2.00 + 200 * 4.50 + (units - 300) * 7.00;
        else
            bill = 100 * 2.00 + 200 * 4.50 + 200 * 7.00 + (units - 500) * 10.00;

        if(bill > 1000)
            bill = bill + bill * 0.05;
    }

    void display()
    {
        System.out.println("Name: " + name);
        System.out.println("Units Consumed: " + units);
        System.out.printf("Bill Amount: Rs. %.2f\n", bill);
    }

    public static void main(String args[])
    {
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter name: ");
        String n = sc.nextLine();
        System.out.print("Enter units: ");
        int u = sc.nextInt();
        ElectricBill obj = new ElectricBill(n, u);
        obj.calculateBill();
        obj.display();
    }
}

import java.util.Scanner;

class PigLatin
{
    public static void main(String args[])
    {
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter a sentence: ");
        String sen = sc.nextLine().toUpperCase().trim();

        String shortest = "", longest = "", pigSentence = "";
        String remaining = sen;

        while(remaining.length() > 0)
        {
            int sp = remaining.indexOf(' ');
            String word;
            if(sp == -1) { word = remaining; remaining = ""; }
            else { word = remaining.substring(0, sp); remaining = remaining.substring(sp + 1).trim(); }

            if(shortest.length() == 0 || word.length() < shortest.length()) shortest = word;
            if(word.length() > longest.length()) longest = word;

            int vowelIdx = -1;
            for(int i = 0; i < word.length(); i++)
            {
                char ch = word.charAt(i);
                if(ch == 'A' || ch == 'E' || ch == 'I' || ch == 'O' || ch == 'U')
                { vowelIdx = i; break; }
            }

            String pigWord;
            if(vowelIdx == 0) pigWord = word + "AY";
            else if(vowelIdx > 0) pigWord = word.substring(vowelIdx) + word.substring(0, vowelIdx) + "AY";
            else pigWord = word + "AY";

            if(pigSentence.length() > 0) pigSentence += " ";
            pigSentence += pigWord;
        }

        System.out.println("Shortest word: " + shortest);
        System.out.println("Longest word: " + longest);
        System.out.println("Pig Latin: " + pigSentence);
    }
}

import java.util.Scanner;

class SpecialNumbers
{
    public static void main(String args[])
    {
        Scanner sc = new Scanner(System.in);
        System.out.println("1. Neon  2. Happy  3. Pronic");
        System.out.print("Enter choice: ");
        int choice = sc.nextInt();

        switch(choice)
        {
            case 1:
                System.out.print("Enter number: ");
                int n = sc.nextInt();
                int sq = n * n, digitSum = 0, temp = sq;
                while(temp > 0) { digitSum += temp % 10; temp /= 10; }
                System.out.println(digitSum == n ? n + " is a Neon Number" : n + " is NOT a Neon Number");
                break;

            case 2:
                System.out.print("Enter number: ");
                int num = sc.nextInt();
                int orig = num;
                while(num != 1 && num != 4)
                {
                    int sumSq = 0, t = num;
                    while(t > 0) { int d = t % 10; sumSq += d * d; t /= 10; }
                    num = sumSq;
                }
                System.out.println(num == 1 ? orig + " is a Happy Number" : orig + " is NOT a Happy Number");
                break;

            case 3:
                System.out.print("Enter number: ");
                int p = sc.nextInt();
                boolean isPronic = false;
                for(int i = 0; i * (i + 1) <= p; i++)
                {
                    if(i * (i + 1) == p) { isPronic = true; System.out.println(p + " is Pronic (" + i + " x " + (i+1) + ")"); break; }
                }
                if(!isPronic) System.out.println(p + " is NOT a Pronic Number");
                break;

            default: System.out.println("Invalid choice");
        }
    }
}

import java.util.Scanner;

class NameSorter
{
    public static void main(String args[])
    {
        Scanner sc = new Scanner(System.in);
        String names[] = new String[10];
        System.out.println("Enter 10 names:");
        for(int i = 0; i < 10; i++) names[i] = sc.nextLine().trim();

        // Selection Sort
        for(int i = 0; i < 9; i++)
        {
            int minIdx = i;
            for(int j = i + 1; j < 10; j++)
                if(names[j].compareToIgnoreCase(names[minIdx]) < 0) minIdx = j;
            String temp = names[i]; names[i] = names[minIdx]; names[minIdx] = temp;
        }

        System.out.println("\nSorted names:");
        for(int i = 0; i < 10; i++) System.out.println(names[i]);

        // Binary Search
        System.out.print("\nEnter name to search: ");
        String key = sc.nextLine().trim();
        int low = 0, high = 9, pos = -1;
        while(low <= high)
        {
            int mid = (low + high) / 2;
            int cmp = key.compareToIgnoreCase(names[mid]);
            if(cmp == 0) { pos = mid; break; }
            else if(cmp < 0) high = mid - 1;
            else low = mid + 1;
        }
        System.out.println(pos != -1 ? key + " found at position " + (pos + 1) : key + " not found");
    }
}

import java.util.Scanner;

class MatrixOperations
{
    public static void main(String args[])
    {
        Scanner sc = new Scanner(System.in);
        int mat[][] = new int[4][4];
        System.out.println("Enter elements of 4x4 matrix:");
        for(int i = 0; i < 4; i++)
            for(int j = 0; j < 4; j++) mat[i][j] = sc.nextInt();

        // Display original
        System.out.println("\nOriginal Matrix:");
        for(int i = 0; i < 4; i++)
        { for(int j = 0; j < 4; j++) System.out.print(mat[i][j] + "\t"); System.out.println(); }

        // Boundary sum
        int boundarySum = 0;
        for(int i = 0; i < 4; i++)
            for(int j = 0; j < 4; j++)
                if(i == 0 || i == 3 || j == 0 || j == 3) boundarySum += mat[i][j];
        System.out.println("\nBoundary sum = " + boundarySum);

        // Diagonal sums
        int leftDiag = 0, rightDiag = 0;
        for(int i = 0; i < 4; i++) { leftDiag += mat[i][i]; rightDiag += mat[i][3-i]; }
        // 4x4: even size, no intersection
        System.out.println("Left diagonal = " + leftDiag);
        System.out.println("Right diagonal = " + rightDiag);
        System.out.println("Both diagonals (unique) = " + (leftDiag + rightDiag));

        // Replace boundary with row number
        System.out.println("\nModified Matrix:");
        for(int i = 0; i < 4; i++)
        {
            for(int j = 0; j < 4; j++)
            {
                if(i == 0 || i == 3 || j == 0 || j == 3) System.out.print((i+1) + "\t");
                else System.out.print(mat[i][j] + "\t");
            }
            System.out.println();
        }
    }
}

import java.util.Scanner;

class MethodOverload
{
    void display(int n)
    {
        int num = 1;
        for(int i = 1; i <= n; i++)
        {
            for(int j = 1; j <= i; j++) { System.out.print(num + " "); num++; }
            System.out.println();
        }
    }

    void display(String s)
    {
        String upper = s.toUpperCase();
        boolean isUnique = true;
        String repeated = "";
        for(int i = 0; i < upper.length(); i++)
        {
            char ch = upper.charAt(i);
            for(int j = i + 1; j < upper.length(); j++)
            {
                if(ch == upper.charAt(j))
                {
                    isUnique = false;
                    if(repeated.indexOf(ch) == -1) repeated += ch;
                    break;
                }
            }
        }
        if(isUnique) System.out.println(s + " is a Unique String");
        else System.out.println(s + " is NOT Unique. Repeated: " + repeated);
    }

    void display(int a, int b)
    {
        System.out.print("Primes between " + a + " and " + b + ": ");
        int count = 0;
        for(int i = a; i <= b; i++)
        {
            if(i <= 1) continue;
            boolean isPrime = true;
            for(int j = 2; j <= Math.sqrt(i); j++)
                if(i % j == 0) { isPrime = false; break; }
            if(isPrime) { System.out.print(i + " "); count++; }
        }
        System.out.println("\nCount: " + count);
    }

    public static void main(String args[])
    {
        MethodOverload obj = new MethodOverload();
        obj.display(4);
        obj.display("SCHOOL");
        obj.display(10, 30);
    }
}