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Create a Star Pattern in Java.

I am working on a simple star pattern program in Java. I have the code running but it is not doing what it's supposed to. My code is:
public class q3 {
public static void main(String[] args) {
for (int i = 10; i >= 1; i--){
for (int j = i; j >= 1; j--){
System.out.print("*");
}
System.out.println("");
}
}
}
Output:
$$$$$$$$$$
$$$$$$$$$
$$$$$$$$
$$$$$$$
$$$$$$
$$$$$
$$$$
$$$
$$
$
What I want is something like this below:
$
$$
$$$
$$$$
$$$$$
..........
$$$$$$$$$$
Can someone please help me figure out how I would get the above pattern. Thank You.

Try this :
public static void main(String[] args) {
final int length = 10;
for (int i = 1; i < length; i++) {
//Print spaces first
for (int j = length - 1; j > i; j--) {
System.out.print(" ");
}
//Then print "*"
for (int j = 1; j <= i; j++) {
System.out.print("*");
}
System.out.println();
}
}
Output is for length = 10 :
*
**
***
****
*****
******
*******
********

We can achieve this pattern using a single for loop:
char [] mirrorascval = new char[5];
for (int i = 4; i >= 0; i--) {
mirrorascval[i] ='*';
System.out.println(mirrorascval);
}

class StarTriangle {
public static void main(String[] args) {
int i, j, k;
for (i = 8; i >= 1; i--) {
for (j = 1; j < i; j++) {
System.out.print(" ");
}
for (k = 8; k >= i; k--) {
System.out.print("*");
}
System.out.println();
}
}
}

public void starPrint(){
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 5 - i; j++) {
System.out.print(" ");
}
for (int k = 0; k <= i; k++) {
System.out.print("*");
}
System.out.println();
}
}

import java.util.*;
public class firstStar {
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner S=new Scanner(System.in);
int n=S.nextInt();
int i=1;
while(i<=n) {
int j=1;
while(j<=i) {
System.out.print("*");
j=j+1;
}
System.out.println();
i=i+1;
}
}
}

package star.pattern;
import java.util.Scanner;
public class StarPattern {
public static void main(String[] args) {
Scanner scn=new Scanner(System.in);
int l;
System.out.print("Enter No Of Line You Want:- ");
l=scn.nextInt();
int x=1;
while(x<=l){
int j=x;
while(j<l){
System.out.print(" ");
j++;
}
int y=1;
while(y<=x){
System.out.print("*");
y++;
}
System.out.println("");
x++;
}
}
}

public class q3 {
public static void main(String[] args) {
for (int i = 1; i <=10; i++){
for (int j = 10; j >= i; j--){
System.out.print("*");
}
System.out.println("");
}
}
}

Try this...
int i, j, k=8;
for(i=0; i<5; i++)
{
for(j=0; j<k; j++)
{
System.out.print(" ");
}
k = k - 2;
for(j=0; j<=i; j++)
{
System.out.print("* ");
}
System.out.println();
}

Pyramid of asterisk

I am trying to write code using a for loop to print a pyramid of asterisks. The height of the pyramid should be determined by the user input and should look like:
ex: input of 3
*
**
***
**
*
import java.util.Scanner;
public class Homework6_Project2 {
public static void main(String[] args) {
Scanner keyboard = new Scanner(System.in);
int triangleHeight = keyboard.nextInt();
int i;
int j;
for (i = triangleHeight; i >= 1; i--) {
for (j = i; j >= 1; j--) {
System.out.print("*");
}
System.out.println();
}
}
}
edit: I was forgetting the code for the bottom half where I needed to use the ++ increment operator.

You need another looping to print the upper pyramids.
Something like:
for(i = 1; i < triangleHeight; i++) {
for (j = 1; j <= i; j++) {
System.out.print("*");
}
System.out.println();
}
You can check this code which gave me the following output for input 3:
*
**
***
**
*

public class PyramidOfAsterisk {
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
java.util.Scanner keyboard = new java.util.Scanner(System.in);
int pyramidHeight = keyboard.nextInt();
for(int i = 1; i <= pyramidHeight; i++){
for(int j=1; j <= i; j++){
System.out.print('*');
}
System.out.println();
}
for(int i = pyramidHeight - 1; i > 0; i--){
for(int j=i; j > 0; j--){
System.out.print('*');
}
System.out.println();
}
}

How to make a trust for the last christmas tree?

public class Xmas{
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("program.");
System.out.print("Height: ");
int n = sc.nextInt();
if (n <= 0) {
System.out.println("Height can only be positive.");
}
else {
System.out.print("Levels: ");
int sz = sc.nextInt();
if (sz <= 0) {
System.out.println("Levels can only be positive.");
}
else
for (int s = 0; s < sz; s++) {
for(int i=0; i<n; i++) {
for(int j=0; j<n-i-1; j++) {
System.out.print(" ");
}
for(int k=0; k<=2*i; k++) {
System.out.print("*");
}
System.out.println();
}
}
}
}
}
I need this for the last tree:
I have to do a 3*3 strut in the middle of the tree.
*
***
*****
*******
*********
***
***
***
I have no idea how to do that.
please help me and give me a code! Thanks!

The code below is maybe that what you are searching for. The additional loop prints the asterisks depending on the height. Three lines with 3 asterisks.
import java.util.Scanner;
public class Test {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("program.");
System.out.print("Height: ");
int n = sc.nextInt();
if (n <= 0) {
System.out.println("Height can only be positive.");
} else {
System.out.print("Levels: ");
int sz = sc.nextInt();
if (sz <= 0) {
System.out.println("Levels can only be positive.");
} else {
for (int s = 0; s < sz; s++) {
for (int i = 0; i < n; i++) {
for (int j = 0; j < n - i - 1; j++) {
System.out.print(" ");
}
for (int k = 0; k <= 2 * i; k++) {
System.out.print("*");
}
System.out.println();
}
}
}
for (int i = 0; i < 3; i++) {
for (int j = 0; j < n - 1; j++) {
if (j == n - 2) {
System.out.println("***");
continue;
}
System.out.print(" ");
}
}
}
}
}

Creating a Christmas Tree using for loops

I am trying to make a christmas tree using for loops and nested for loops. For me to do that I need to be able to make a pyramids with *. I have tried countless times and I am having problems making one. Here is my code:
for(int i=1;i<=10;i++){
for(int j=10;j>i;j--){
System.out.println(" ");
}
for(int k=1;k<=i;k++){
System.out.print("*");
}
for(int l=10;l<=1;l++){
for(int h=1;h<=10;h++){
System.out.print(" ");
}
}
System.out.println();
}
What I am trying to do is:
*
***
*****
*******

Try this much simpler code:
public class ChristmasTree {
public static void main(String[] args) {
for (int i = 0; i < 10; i++) {
for (int j = 0; j < 10 - i; j++)
System.out.print(" ");
for (int k = 0; k < (2 * i + 1); k++)
System.out.print("*");
System.out.println();
}
}
}
It uses 3 loops:
first one for the number of rows,
second one for printing the spaces,
third one for printing the asterisks.

You can do it with simple logic
for (int i = 0; i < 4; i++)
System.out.println(" *******".substring(i, 4 + 2*i));

import java.util.Scanner;
public class cmastree{
public static void main (String[]args){
Scanner keyboard=new Scanner (System.in);
int j;
System.out.println ("Enter a number");
j=keyboard.nextInt();
/*take the above part out and change the j variable if you want to set
the size*/
for(int i=1; i<=j; i+=2){
int numSpaces = (j-i)/2;
for (int k=0; k<numSpaces; k++){
System.out.print(" ");
}
for(int k=0; k<numSpaces; k++){
System.out.print("*");
}
System.out.println();
}
}
}

public class ChrismasTree {
public static void main(String[] args) {
int sizeOfTree = 9;
double remainderVal = sizeOfTree % 2 ;
double ans = sizeOfTree / 2 ;
if (remainderVal == 0) {
System.out.println("Invalid number enter 9,19 calculat rest yourself u looser ..");
System.exit(0);
}
int middlePos = (int) Math.round(ans + .5);
for (int i = 0; i <= sizeOfTree; i++) {
int lStar = middlePos - i;
int rStar = middlePos + i;
if (lStar < 1) {
break;
}
printleaves(lStar, rStar, sizeOfTree);
}
}
public static void printleaves(int a,int b, int size){
System.out.println();
for (int i = 1; i <= size; i++) {
if (i > a && i < b ){
System.out.print("*");
}else System.out.print(" ");
}
}
}

public class Stars {
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
Scanner s=new Scanner(System.in);
System.out.println("Enter Row/Column Value::");
int i,j,k,n;
n=s.nextInt();
for(i=1; i<n; i++){
for(j=n+(n/2); j>i; j--){
System.out.print(" ");}
for(k=1; k<=2*i-1; k++){
System.out.print("*");}
System.out.println("");
}
for(i=1; i<n+(n/2); i++){
for(j=n+(n/2); j>i; j--){
System.out.print(" ");}
for(k=1; k<=2*i-1; k++){
System.out.print("*");}
System.out.println("");
}
for(i=1; i<n-(n/2); i++){
for(j=n+(n/2); j>1; j--){
System.out.print(" ");}
for(k=n/2; k<=(n/2)+1; k++){
System.out.print("*");}
System.out.println("");
}
}
}

public class ChristmasTree {
public static void printStars(int number) {
for (int i = 1; i <= number; i++) {
System.out.print("*");
}
System.out.println("");
}
public static void printSpaces(int number) {
for (int i = 0; i < number; i++) {
System.out.print(" ");
}
}
public static void christmasTree(int height) {
for (int i = 1; i <= height; i++) {
printSpaces(height - i);
printStars(i + (i - 1));
}
}
public static void main(String[] args) {
// int x = pick some number, but not TOO big )))
christmasTree(x);
}
}

def fist(n)
k=2*n-2
for i in range(0,n):
for j in range(0,k):
k=k-1
print(end=" ')
for j in range(0,i+1):
print("*",end=" ")
print()
def second(n)
k=2*n-2
for i in range(0,n):
for j in range(0,k):
k=k-1
print(end=" ')
for j in range(0,i+1):
print("*",end=" ")
print()
def stem(m)
k=11
for i in range(0,5):
for j in range(0,k):
print(end=" ")
for j in range(0,3):
print("*",end=" ")
print()
first(7)
second(7)
steam(3)

A program that prints the following pattern

I have to code a program to print this output:
1
212
32123
4321234
543212345
I have successfully coded this portion of the pattern:
1
12
123
1234
12345
However, I am not reaching the second portion. Here's my code:
for(int i=1; i<=5; i++) {
for(int j=1; j<=i; j++) {
System.out.print(j);
}
System.out.println();
}

Why not recursive? Just because it's fun ;)
public static void main(String args[]) {
System.out.println(pyramid(5));
}
public static String pyramid(int rank) {
if (rank == 1) {
return "1\n";
}
return pyramid(rank - 1) + mirror(rank) + "\n";
}
public static String mirror(int rank) {
if (rank == 1) {
return "1";
} else {
return rank + mirror(rank - 1) + rank;
}
}

You just need another j for loop before your current j for loop that counts down from 5 to (but not including) 1. Decide whether to print a space or j itself, depending on if j is greater than i.
for (int j=5; j > 1; j--) {
if (j > i)
System.out.print(' ');
else
System.out.print(j);
}

package recAaA;
public class testA {
static void rec(int startVal, int endVal)
{
if(startVal==0)startVal=-2;
if(startVal<-endVal) return;
System.out.print(Math.abs(startVal));
rec(startVal-1,endVal);
}
public static void main(String[] args) {
// TODO Auto-generated method stub
int imax=5;
for(int i=1;i<imax+1;i++)
{
for(int j=0;j<imax+1-i;j++)
{
System.out.print(" ");
}
rec(i,i);
System.out.println();
}
}
}
Output:
1
212
32123
4321234
543212345
if you give i to startVal and i+1 to endVal, the output becomes
12
2123
321234
43212345
5432123456

As someone already noted, you can accomplish this easily with a double for-loop, one counting down from i, one counting up:
for(int i=1; i<=5; i++) {
for(int j=i; j>=2; j--) {
System.out.print(j);
}
for(int j=1; j<=i; j++) {
System.out.print(j);
}
System.out.println();
}
You can also accomplish the same thing in a single for loop if you don't print right away. For example you can build an StringBuffer with one, then add the numbers on either side until i==j, and then print outside of the inner loop.
for(int i=1; i<=5; i++) {
StringBuffer buffer = new StringBuffer();
buffer.append(1);
for(int j=2; j<=i; j++) {
buffer.insert(0, j);
buffer.append(j);
}
System.out.println(buffer);
}

Here's code that outputs the numbers; all you have to do is fix the spacing.
for (int i = 1; i <= 9; i++) {
BigInteger b =
BigInteger.TEN.pow(2*i-1)
.subtract(BigInteger.ONE)
.divide(BigInteger.valueOf(9))
.multiply(BigInteger.valueOf(i+1))
.subtract(BigInteger.TEN.pow(i)
.subtract(BigInteger.ONE)
.divide(BigInteger.valueOf(9))
.pow(2));
System.out.println(b);
}
That is, for each integer in the range 1-9, it prints ((102n-1-1)/9)(n+1)-((10n-1)/9)2. Very simple.

/* Basically logic is that in a horizontal line upto the mid ,the number is decrementing and after the mid, the number starts incrementing
*/
public class java {
public static void main(String[] args) throws IOException {
int n;
InputStreamReader io = new InputStreamReader(System.in);
BufferedReader br = new BufferedReader(io);
System.out.println("Enter the height in the number of lines vertically");
n = Integer.parseInt(br.readLine());
for (int i = 1; i <= n; i++) {
int k = i;
for (int j = 1; j <= 2 * i - 1; j++) {
System.out.print(k);
if (j >= (((2 * i - 1) / 2) + 1))
k++;
else if(j<(2*i-1)/2+1) k--;
}
System.out.println();
}
}
}
I hope this will help !

import java.util.*;
public class test {
public static void main(String[] args) {
int i,j,k,l,n,a;
Scanner sc = new Scanner(System.in);
n = sc.nextInt();
a = n;
for(i=1 ; i<=n ; i++){
for(j=a ; j>1 ; j--){
System.out.print(" ");
}
for(k=i ; k!=0; k--){
System.out.print(k);
}
a--;
for(l=2; l<=i ; l++){
System.out.print(l);
}
System.out.println(" ");
}
}
}

for(int i=1;i<=100; i++) {
for(int j=100;j>i;j--)
System.out.print(" ");
for(int k=i;k>1;k--)
System.out.print(k+" ");
for(int j=1; j<=i; j++)
System.out.print(j+" ");
System.out.println();
}

public class test {
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner in = new Scanner(System.in);
System.out.print("Enter no ");
int n=in.nextInt();
for(int i=1;i<=n;i++)
{
int l=n-i;
while(l!=0)
{
System.out.print(" ");
l--;
}
for(int j=i;j>=2;j--)
{
System.out.print(j);
}
for(int k=1;k<=i;k++)
{
System.out.print(k);
}
System.out.println();
}
}
}