Assignment Questions
Question 1
Write a program to generate the following output.
@
@ #
@ # @
@ # @ #
@ # @ # @
public class KboatPattern
{
public static void main(String args[]) {
for (int i = 1; i <= 5; i++) {
for (int j = 1; j <= i; j++) {
if (j % 2 == 0)
System.out.print("# ");
else
System.out.print("@ ");
}
System.out.println();
}
}
}Output
Question 2(i)
Write a program in Java to display the following patterns.
1
2 3
4 5 6
7 8 9 10
11 12 13 14 15
public class KboatPattern
{
public static void main(String args[]) {
int a = 1;
for (int i = 1; i <= 5; i++) {
for (int j = 1; j <= i; j++) {
System.out.print(a++ + "\t");
}
System.out.println();
}
}
}Output
Question 2(ii)
Write a program in Java to display the following patterns.
1 * * * *
* 2 * * *
* * 3 * *
* * * 4 *
* * * * 5
public class KboatPattern
{
public static void main(String args[]) {
char ch = '*';
for (int i = 1; i <= 5; i++) {
for (int j = 1; j <= 5 ; j++) {
if(i == j)
System.out.print(i + " ");
else
System.out.print(ch + " ");
}
System.out.println();
}
}
}Output
Question 2(iii)
Write a program in Java to display the following patterns.
#
* *
# # #
* * * *
# # # # #
public class KboatPattern
{
public static void main(String args[]) {
char ch1 = '#', ch2 = '*';
for (int i = 1; i <= 5; i++) {
for (int j = 1; j <= i; j++) {
if (i % 2 == 0)
System.out.print(ch2 + " ");
else
System.out.print(ch1 + " ");
}
System.out.println();
}
}
}Output
Question 2(iv)
Write a program in Java to display the following patterns.
1 * * * *
2 2 * * *
3 3 3 * *
4 4 4 4 *
5 5 5 5 5
public class KboatPattern
{
public static void main(String args[]) {
for (int i = 1; i <= 5; i++) {
for (int j = 1; j <= i; j++) {
System.out.print(i);
}
for (int k = 1; k <= 5 - i; k++) {
System.out.print('*');
}
System.out.println();
}
}
}Output
Question 2(v)
Write a program in Java to display the following patterns.
$ $ $ $ 5
$ $ $ 4
$ $ 3
$ 2
1
public class KboatPattern
{
public static void main(String args[]) {
char ch = '$';
for (int i = 5; i >= 1; i--) {
for (int j = i-1; j >= 1 ; j--)
System.out.print(ch + " ");
System.out.print(i);
System.out.println();
}
}
}Output
Question 2(vi)
Write a program in Java to display the following patterns.
A B C D E
A B C D
A B C
A B
A
public class KboatPattern
{
public static void main(String args[]) {
for (int i = 69; i >= 65; i--) {
for (int j = 65; j <= i; j++) {
System.out.print((char)j);
}
System.out.println();
}
}
}Output
Question 2(vii)
Write a program in Java to display the following patterns.
5 4 3 2 1
4 3 2 1
3 2 1
2 1
1
public class KboatPattern
{
public static void main(String args[]) {
for (int i = 5; i >= 1; i--) {
for (int j = i; j >= 1; j--)
System.out.print( j + " ");
System.out.println();
}
}
}Output
Question 2(viii)
Write a program in Java to display the following patterns.
I
I C
I C S
I C S E
public class KboatPattern
{
public static void main(String args[]) {
String str = "ICSE";
int len = str.length();
for(int i = 0; i < len; i++) {
for(int j = 0; j <= i; j++) {
System.out.print(str.charAt(j) + " ");
}
System.out.println();
}
}
}Output
Question 2(ix)
Write a program in Java to display the following patterns.
1 2 3 4 5
1 2 3 4
1 2 3
1 2
1
1 2
1 2 3
1 2 3 4
1 2 3 4 5
public class KboatPattern
{
public static void main(String args[]) {
for(int i = 5; i >= 1; i--) {
for(int j = 1; j <= i; j++)
System.out.print(j + " ");
System.out.println();
}
for(int i = 2; i <= 5; i++) {
for(int j = 1; j <= i; j++)
System.out.print(j + " ");
System.out.println();
}
}
}Output
Question 2(x)
Write a program in Java to display the following patterns.
1 2 3 4 5
2 3 4 5
3 4 5
4 5
5
4 5
3 4 5
2 3 4 5
1 2 3 4 5
public class KboatPattern
{
public static void main(String args[]) {
for (int i = 1; i <= 5; i++)
{
for (int j = i; j <= 5; j++) {
System.out.print(j);
}
System.out.println();
}
for (int k = 1; k <= 4; k++) {
for (int l = 5 - k; l <= 5; l++) {
System.out.print(l);
}
System.out.println();
}
}
}Output
Question 3(i)
Distinguish between the following:
break statement and labelled break statement
Answer
| break statement | labelled break statement |
|---|---|
| The break statement is used to take the control out of the loop control structure immediately enclosing it. | Labelled break statement transfers program control out of the code block whose label is specified as its target. |
Syntax:break; | Syntax:break <label>; |
| For example, for (int i = 1; i <= 3; i++) { for(int j = 1; j <= 2; j++) { if (i == 2) { break; } System.out.println("Iteration value of inner loop: " + j); } System.out.println(); } | For example, outer: for (int i = 1; i <= 3; i++) { for(int j = 1; j <= 2; j++) { if (i == 2) { System.out.println("Terminating the Outer-loop"); break outer; } System.out.println("i =" + i +" ; j =" + j); } |
Question 3(ii)
Distinguish between the following:
continue statement and labelled continue statement
Answer
| continue statement | labelled continue statement |
|---|---|
| continue statement is used to skip the current iteration of a loop and move on to the next iteration. | A labelled continue statement skips the current iteration of an outer loop by using a label before the loop and including the same label in continue statement. |
Syntax:continue; | Syntax:continue <label>; |
| For example, for (int i = 0; i <= 3; i++) { System.out.println("i =" + i); for(int j = 0; j < 3; j++) { if (i == 2) { continue; } System.out.print("j = " + j + " "); } System.out.println(); } | For example, outerLoop: for (int i = 0; i <= 3; i++) { for(int j = 0; j < 3; j++) { if (i == 2) { continue outerLoop; System.out.println("i =" + i +" ; j =" + j); } } } |
Question 4
Write a program to print the series given below.
8 88 888 8888 88888 888888
public class Kboat8Series
{
public static void main(String args[]) {
for (int i = 1; i <= 6; i++) {
for (int j = 0; j < i; j++) {
System.out.print('8');
}
System.out.print(' ');
}
}
}Output
Question 5(i)
What will be the value of sum after each of the following nested loops is executed?
int sum = 0;
for (int i = 0; i <= 10; i++)
for (int j = 0; j <= 10; j++)
sum += i ;Answer
Sum = 605
Explanation
The outer loop executes 11 times. For each iteration of outer loop, the inner loop executes 11 times. For every value of j, i is added to sum 11 times. Consider the following table for the value of sum with each value of i and j.
| i | j | Sum | Remarks |
|---|---|---|---|
| 0 | 0 - 10 | 0 | 0 is added to sum 11 times |
| 1 | 0 - 10 | 11 | 1 is added to sum 11 times ⇒ 0 + 11 = 11 |
| 2 | 0 - 10 | 33 | 2 is added to sum 11 times ⇒ 11 + 22 = 33 |
| 3 | 0 - 10 | 66 | 3 is added to sum 11 times ⇒ 33 + 33 = 66 |
| 4 | 0 - 10 | 110 | 4 is added to sum 11 times ⇒ 66 + 44 = 110 |
| 5 | 0 - 10 | 165 | 5 is added to sum 11 times ⇒ 110 + 55 = 165 |
| 6 | 0 - 10 | 231 | 6 is added to sum 11 times ⇒ 165 + 66 = 231 |
| 7 | 0 - 10 | 308 | 7 is added to sum 11 times ⇒ 231 + 77 = 308 |
| 8 | 0 - 10 | 396 | 8 is added to sum 11 times ⇒ 308 + 88 = 396 |
| 9 | 0 - 10 | 495 | 9 is added to sum 11 times ⇒ 396 + 99 = 495 |
| 10 | 0 - 10 | 605 | 10 is added to sum 11 times ⇒ 495 + 110 = 605 |
| 11 | Loop terminates |
Question 5(ii)
What will be the value of sum after each of the following nested loops is executed?
int sum = 0;
for (int i = 1; i <= 3; i++)
for (int j = 1; j <= 3;j++)
sum = sum + (i + j);Answer
Sum = 36
Explanation
The outer loop executes 3 times. For each iteration of outer loop, the inner loop executes 3 times. For every value of j, i + j is added to sum 3 times. Consider the following table for the value of sum with each value of i and j.
| i | j | Sum | sum + (i + j) |
|---|---|---|---|
| 1 | 1 | 2 | 0 + 1 + 1 |
| 2 | 5 | 2 + 1 + 2 | |
| 3 | 9 | 5 + 1 + 3 | |
| 2 | 1 | 12 | 9 + 2 + 1 |
| 2 | 16 | 12 + 2 + 2 | |
| 3 | 21 | 16 + 2 + 3 | |
| 3 | 1 | 25 | 21 + 3 + 1 |
| 2 | 30 | 25 + 3 + 2 | |
| 3 | 36 | 30 + 3 + 3 | |
| 4 | Loop terminates |
Question 6
Write a program to generate a triangle or an inverted triangle till n terms based upon the user's choice of triangle to be displayed.
Example 1
Input:
Type 1 for a triangle and type 2 for an inverted triangle
1
Enter the number of terms
5
Output:
1
2 2
3 3 3
4 4 4 4
5 5 5 5 5
Example 2
Input:
Type 1 for a triangle and type 2 for an inverted triangle
2
Enter the number of terms
6
Output:
6 6 6 6 6 6
5 5 5 5 5
4 4 4 4
3 3 3
2 2
1
import java.util.Scanner;
public class KboatPattern
{
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
System.out.println("Type 1 for a triangle");
System.out.println("Type 2 for an inverted triangle");
System.out.print("Enter your choice: ");
int ch = in.nextInt();
System.out.print("Enter the number of terms: ");
int n = in.nextInt();
switch (ch) {
case 1:
for (int i = 1; i <= n; i++) {
for (int j = 1; j <= i; j++) {
System.out.print(i + " ");
}
System.out.println();
}
break;
case 2:
for (int i = n; i > 0; i--) {
for (int j = 1; j <= i; j++) {
System.out.print(i + " ");
}
System.out.println();
}
break;
default:
System.out.println("Incorrect Choice");
}
}
}Output
Question 7
Write a program to compute and display factorials of numbers between p and q where p > 0, q > 0, and p > q.
import java.util.Scanner;
public class KboatFactRange
{
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
System.out.print("Enter p: ");
int p = in.nextInt();
System.out.print("Enter q: ");
int q = in.nextInt();
if (p > q && p > 0 && q > 0) {
for (int i = q; i <= p; i++) {
long fact = 1;
for (int j = 1; j <= i; j++)
fact *= j;
System.out.println("Factorial of " + i +
" = " + fact);
}
}
else {
System.out.println("Invalid Input");
}
}
}Output
Question 8
Write a program to determine if an entered number is a Happy Number. A happy number is defined by the following process:
Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number is equal to 1.
For example, 19 is a happy number, as per the following calculation:
12 + 92 = 82,
82 + 22 = 68,
62 + 82 = 100,
12 + 02 + 02 = 1
import java.util.Scanner;
public class KboatHappyNumber
{
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
System.out.print("Enter number to check: ");
long num = in.nextLong();
long sum = 0;
long n = num;
do {
sum = 0;
while (n != 0) {
int d = (int)(n % 10);
sum += d * d;
n /= 10;
}
n = sum;
} while (sum > 6);
if (sum == 1) {
System.out.println(num + " is a Happy Number");
}
else {
System.out.println(num + " is not a Happy Number");
}
}
}Output
Question 9
Write a menu driven program that prompts the user to select one of the four triangle patterns (a, b, c, or d). The program then accepts number of rows and prints the selected pattern as shown below:
Enter the size : 8
(a)
#
# #
# # #
# # # #
# # # # #
# # # # # #
# # # # # # #
# # # # # # # #
(b)
# # # # # # # #
# # # # # # #
# # # # # #
# # # # #
# # # #
# # #
# #
#
(c)
# # # # # # # #
# # # # # # #
# # # # # #
# # # # #
# # # #
# # #
# #
#
(d)
#
# #
# # #
# # # #
# # # # #
# # # # # #
# # # # # # #
# # # # # # # #
import java.util.Scanner;
public class KboatTriangleChoice
{
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
System.out.println("Type a for Pattern a");
System.out.println("Type b for Pattern b");
System.out.println("Type c for Pattern c");
System.out.println("Type d for Pattern d");
System.out.print("Enter your choice: ");
char ch = in.next().charAt(0);
System.out.print("Enter the number of terms: ");
int n = in.nextInt();
switch (ch) {
case 'a':
for (int i = 1; i <= n; i++) {
for (int j = 1; j <= i; j++)
System.out.print('#');
System.out.println();
}
break;
case 'b':
for (int i = n; i >= 1; i--) {
for (int j = 1; j <= i; j++)
System.out.print('#');
System.out.println();
}
break;
case 'c':
for (int i = n; i >= 1; i--) {
for (int j = i; j < n; j++)
System.out.print(" ");
for (int k = 0; k < i; k++)
System.out.print('#');
System.out.println();
}
break;
case 'd':
for (int i = n; i >= 1; i--) {
for (int j = 1; j < i; j++)
System.out.print(" ");
for (int k = i; k <= n; k++)
System.out.print('#');
System.out.println();
}
break;
default:
System.out.println("Incorrect choice");
break;
}
}
}Output
Question 10
Write a menu driven program that prompts the user to select one of the four triangle patterns (a, b, c or d). The program then accepts number of rows and prints the selected pattern as shown below:
Enter the size: 8
(a)
1
1 2
1 2 3
1 2 3 4
1 2 3 4 5
1 2 3 4 5 6
1 2 3 4 5 6 7
1 2 3 4 5 6 7 8
(b)
1 2 3 4 5 6 7 8
1 2 3 4 5 6 7
1 2 3 4 5 6
1 2 3 4 5
1 2 3 4
1 2 3
1 2
1
(c)
1
1 2
1 2 3
1 2 3 4
1 2 3 4 5
1 2 3 4 5 6
1 2 3 4 5 6 7
1 2 3 4 5 6 7 8
(d)
1 2 3 4 5 6 7 8
1 2 3 4 5 6 7
1 2 3 4 5 6
1 2 3 4 5
1 2 3 4
1 2 3
1 2
1
import java.util.Scanner;
public class KboatTriangleChoice
{
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
System.out.println("Type a for Pattern a");
System.out.println("Type b for Pattern b");
System.out.println("Type c for Pattern c");
System.out.println("Type d for Pattern d");
System.out.print("Enter your choice: ");
char ch = in.next().charAt(0);
System.out.print("Enter the number of terms: ");
int n = in.nextInt();
switch (ch) {
case 'a':
for (int i = 1; i <= n; i++) {
for (int j = 1; j <= i; j++)
System.out.print(j);
System.out.println();
}
break;
case 'b':
for (int i = n; i >= 1; i--) {
for (int j = i; j < n; j++)
System.out.print(" ");
for (int k = 1; k <= i; k++)
System.out.print(k);
System.out.println();
}
break;
case 'c':
for (int i = 1; i <= n; i++) {
for (int j = i; j < n; j++)
System.out.print(" ");
for (int k = 1; k <= i; k++)
System.out.print(k);
System.out.println();
}
break;
case 'd':
for (int i = n; i >= 1; i--) {
for (int j = 1; j <= i; j++)
System.out.print(j);
System.out.println();
}
break;
default:
System.out.println("Incorrect choice");
break;
}
}
}Output
Question 11
Write a program that computes sin x and cos x by using the following power series:
sin x = x - x3/3! + x5/5! - x7/7! + ......
cos x = 1 - x2/2! + x4/4! - x6/6! + ......
import java.util.Scanner;
public class KboatSeries
{
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
System.out.print("Enter x: ");
int x = in.nextInt();
double sinx = 0, cosx = 0;
int a = 1;
for (int i = 1; i <= 20; i += 2) {
long f = 1;
for (int j = 1; j <= i; j++)
f *= j;
double t = Math.pow(x, i) / f * a;
sinx += t;
a *= -1;
}
a = 1;
for (int i = 0; i <= 20; i += 2) {
long f = 1;
for (int j = 1; j <= i; j++)
f *= j;
double t = Math.pow(x, i) / f * a;
cosx += t;
a *= -1;
}
System.out.println("Sin x = " + sinx);
System.out.println("Cos x = " + cosx);
}
}Output
