Java out patterns - java

I'm currently trying to get this output using nested loops:
For the life of me I cannot figure out how to get the # signs to increment by +2 each time. Any help would be greatly appreciated!
public class PrintPatterns {
public static void main(String[] args) {
pattern1();
}
private static void pattern1() {
for (int i = 1; i <= 10; i++) {
for (int j = 0; j < 10; j += 2); {
System.out.print("# ");
}
for (int j = 0; j < 2; j++) {
System.out.print(". ");
}
for (int j = 1; j < 10 - i; j++) {
System.out.print("x ");
}
System.out.println();
}
}
}

This code does what you want:
private static void pattern1() {
StringBuilder stringBuilder = new StringBuilder();
for (int ats = 2; ats <= 10; ats += 2) {
for (int j = 0; j < ats; j++) {
stringBuilder.append("# ");
}
stringBuilder.append(". . ");
for (int j = 0; j <= 10 - ats; j++) {
stringBuilder.append("x ");
}
stringBuilder.append("\n");
}
System.out.println(stringBuilder.toString());
}
One mistake you did in your code is that you put a ; after your for loop, this will end the loop right there.
Also do not use System.out.println() in loops. As using IO will slow down your application. Use StringBuilder to build strings and then output all at once.

Instead of:
for (int j = 0; j < 10; j += 2); {
System.out.print("# ");
}
Try:
for (int j = 0; j < 2 * i; j += 1) {
System.out.print("# ");
}

public class PrintPatterns
{
public static void main(String[] args)
{
pattern1();
}
private static void pattern1()
{
for(int i = 1; i <= 10; i++)
{
for(int j = 1; j < i+2; j++)
{
System.out.print("# ");
}
for(int j = 0; j < 2; j++)
{
System.out.print(". ");
}
for(int k = 10-i; k > 0; k--)
{
System.out.print("x ");
}
System.out.println();
}
}
}

Related

About diamond generation code in Java

This is the work that i done so far, i'manage to do is just create a triangle,So how can i extend this to create a Diamond pattern
class Diamond {
public static void main(String[] args) {
for (int i = 1; i < 10; i += 2) {
for (int j = 0; j < 9 - i / 2; j++)
System.out.print(" ");
for (int j = 0; j < i; j++)
System.out.print("*");
System.out.print("\n");}
}
You have to change the program like this, first you have to keep in mind
that you have to create empty spaces, then only you'll be able
to create this pattern,this is sample code.You have to create an
Upside down triangle, like you done so far,
class Diamond {
public static void main(String[] args) {
for (int i = 1; i < 10; i += 2) {
for (int j = 0; j < 9 - i / 2; j++)
System.out.print(" ");
for (int j = 0; j < i; j++)
System.out.print("*");
System.out.print("\n");
}
for (int i = 7; i > 0; i -= 2) {
for (int j = 0; j < 9 - i / 2; j++)
System.out.print(" ");
for (int j = 0; j < i; j++)
System.out.print("*");
System.out.print("\n");
}
}
}

How can i create these shapes with java

package assignment.pkg3;
import java.util.Scanner;
public class Assignment3 {
public static void main(String[] args) {
Scanner stdIn = new Scanner(System.in);
System.out.print("What integer length do you want: ");
int length = stdIn.nextInt();
for (int i = 0; i < length; i++) {
for (int j = ((length - 1) - i); j > 0; j--) {
System.out.print(" ");
}
for (int a = 0; a <= i; a++) {
System.out.print("*");
}
System.out.println();
}
for (int i = 0; i < length; i++) {
for (int j = 0; j < i; j++) {
System.out.print(" ");
}
for (int a = length; a > i; a--) {
System.out.print("*");
}
for (int b = (length - 1); b > i; b--) {
System.out.print("*");
}
System.out.println();
}
for (int i = 0; i < length; i++) {
for (int j = 0; j <= i; j++) {
for (int k = 0; k < i; k++) {
System.out.print(" ");
}
for (int a = 0; a <= i; a++) {
System.out.print("*");
}
System.out.println();
}
}
}
}
Hi, I need help making this 3rd shape.. I don't even know how to start it. I did the other 3 pretty well. (except I have the spaces wrong on shape D). Can anyone help me find somewhere to start. (BTW I'm in a beginner java class so I can't put anything in there that we haven't learned. So sticking to for loops is basically all we can essentially use lol)
Here is link to pic
Try to execute this one & check -
for (int i = 0; i < length/2; i++){
for (int j = 0; j < length; j++){
System.out.print("*" + " ");
}
System.out.println("");
for (int k = 0; k < length-1; k++){
System.out.print(" " + "*");
}
System.out.println("");
}
Hope this will solve your problem.

I need help writing a program that prints out two shapes on one line using nested loops

Here is what the shapes should look like :
Here is my code so far:
public class Diamonds {
public static void main(String[] args) {
for (int i = 1; i < 10; i += 2) {
for (int j = 0; j < 9 - i / 2; j++) {
System.out.print(" ");
}
for (int j = 0; j < i; j++) {
System.out.print("*");
}
System.out.print("\n");
}
for (int i = 7; i > 0; i -= 2) {
for (int j = 0; j < 9 - i / 2; j++) {
System.out.print(" ");
}
for (int j = 0; j < i; j++) {
System.out.print("*");
}
System.out.print("\n");
}
}
}
I am having trouble getting the second shape
In order to not spoil your fun with this problem, I will explain what you need to do without writing any code.
To get the second shape in there, you would need to add two additional nested for loops into each of the two "outer" loops that you already have.
Loops number three will produce a fixed number of spaces. Note that the distance between the right edge of the first shape and the left edge of the second shape is constant, so your third loops will be easy to code up.
Loops number four will loop like your first loop, but they would change places: the first inner loop from the first outer loop will be the forth inner loop in the second outer loop, and vice versa.
By examining the shape on the right, we can notice that for each N asterisks on the line in the left shape, the right one has 10 - N, so, taking your code and extending it, we can get:
public class Diamonds {
public static final String SPACE = " ";
public static void main(String[] args) {
for (int i = 1; i < 10; i += 2) {
for (int j = 0; j < 9 - i / 2; j++)
System.out.print(" ");
for (int j = 0; j < i; j++)
System.out.print("*");
System.out.print(SPACE);
for (int j = 0; j < 10 - i; j++)
System.out.print("*");
System.out.print("\n");
}
for (int i = 7; i > 0; i -= 2) {
for (int j = 0; j < 9 - i / 2; j++)
System.out.print(" ");
for (int j = 0; j < i; j++)
System.out.print("*");
System.out.print(SPACE);
for (int j = 0; j < 10 - i; j++)
System.out.print("*");
System.out.print("\n");
}
}
}
And if we extract some common code:
public class Diamonds {
public static final String SPACE = " ";
public static void main(String[] args) {
for (int i = 1; i < 10; i += 2) {
drawLine(i);
System.out.print("\n");
}
for (int i = 7; i > 0; i -= 2) {
drawLine(i);
System.out.print("\n");
}
}
private static void drawLine(int i) {
for (int j = 0; j < 9 - i / 2; j++)
System.out.print(" ");
for (int j = 0; j < i; j++)
System.out.print("*");
System.out.print(SPACE);
for (int j = 0; j < 10 - i; j++)
System.out.print("*");
}
}
public class ReverseDiamond {
public static void main(String[] ar) {
int rows = 10;
ReverseDiamond diamond = new ReverseDiamond();
for(int i = 0; i < rows; i++)
diamond.printLine(rows, i);
for(int i = rows - 2; i >= 0; i--)
diamond.printLine(rows, i);
}
private void printLine(int rows, int currRow) {
for(int space = 1; space <= currRow; space++)
System.out.print(" ");
for(int star = 1; star < 2 * (rows - currRow); star++)
System.out.print("*");
System.out.println();
}
}
You may like that :
public class Diamonds {
public static void main(String[] args) {
int totalStars = 9;
int rows = 9;
for (int r = 0,stars=-1,gap=totalStars; r < rows; r++ ) {
stars+= (r<=rows/2) ?2:-2;
gap=totalStars-stars;
printChars(' ', gap);
printChars('*', stars);
printChars(' ', gap);
int gap2=stars+1;
int stars2=gap+1;
printChars(' ', gap2);
printChars('*', stars2);
printChars(' ', gap2);
System.out.println();
}
}
private static void printChars(char c ,int times) {
for (int i = 0; i < times; i++) {
System.out.print(c);
}
}
}
try this :
public static void main(String[] args) {
for (int i = 9; i > 0; i -= 2) {
for (int j = 0; j < 9 - i / 2; j++)
System.out.print(" ");
for (int j = 0; j < i; j++)
System.out.print("*");
System.out.print("\n");
}
for (int i = 2; i < 10; i += 2) {
for (int j = 0; j < 9 - i / 2; j++)
System.out.print(" ");
for (int j = 0; j <= i; j++)
System.out.print("*");
System.out.print("\n");
}
}
output :
*********
*******
*****
***
*
***
*****
*******
*********

Why does my program produce no output while it's compiling fine?

I want to create a two dimensional array. I am able to compile but not able to run
public class Arraytest1 {
public static void main(String[] args) {
int i, j, k = 0;
int test[][] = new int[4][5];
for (i = 0; i < 4; i++) {
for (j = 0; j < 5; j++) {
test[i][j] = k;
k++;
}
}
for (i = 0; i < 4; i++) {
for (j = 0; j < 5; k++)
System.out.print(test[i][j] + " ");
System.out.println();
}
}
}
You have an endless loop: for(j=0;j<5;k++), you have to write for(j=0;j<5;j++)
You increment k instead of j
You have an endless loop. You are incrementing k instead of j:
for(j=0;j<5;k++)
You should change it both times to
for(j=0;j<5;j++)
Here... this should work. Just change your sub-loops making it j++ instead of k++ both top and bottom
public static void main(String[] args) {
int i, j, k = 0;
int test[][] = new int[4][5];
for (i = 0; i < 4; i++) {
for (j = 0; j < 5; j++) {
test[i][j] = k;
k++;
}
}
for (i = 0; i < 4; i++) {
for (j = 0; j < 5; j++)
System.out.print(test[i][j] + " ");
System.out.println();
}
}
I think you've mixed up the k and j variables in the second for-loop "block". When I alter it to:
...
for (i = 0; i < 4; i++) {
for (j = 0; j < 5; j++)
System.out.print(test[i][j] + " ");
System.out.println();
}
...
I get the following printed to my console:
0 1 2 3 4
5 6 7 8 9
10 11 12 13 14
15 16 17 18 19
Is it what you wanted?
public class Arraytest1 {
public static void main(String[] args) {
int i, j, k = 0;
int test[][] = new int[4][5];
for (i = 0; i < 4; i++) {
for (j = 0; j < 5; j++) {
test[i][j] = k;
k++;
}
}
for (i = 0; i < 4; i++) {
for (j = 0; j < 5; j++) {
System.out.print(test[i][j] + " ");
System.out.println();
}
}
}
}
you can resolve this problem

why does the for-loop go through the args three times?

I want to know why the for-loop counts through the args three times and doesn't stop after the first loop? this is my code :
public class test2 {
public static void main(String[] args) {
int N = args.length;
int[] x = new int[N];
int count = 0;
for (int i = 0; i < x.length; i++) {
x[i] = Integer.parseInt(args[i]);
}
for (int i = 0; i < N; i++) {
for (int j = i+1; j < N; j++) {
if (x[j] != x[j-1]) {
count++;
}
System.out.println(count);
}
}
System.out.println(N-count);
}
}
I think you mean to do this:
for (int j = 1; j < N; j++) {
if (x[j] != x[j-1]) {
count++;
}
System.out.println(count);
}
System.out.println(N-count);
instead of:
for (int i = 0; i < N; i++) {
for (int j = i+1; j < N; j++) {
if (x[j] != x[j-1]) {
count++;
}
System.out.println(count);
}
}
System.out.println(N-count);

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