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Input strings into 2d array

Trying to make a histogram, but the loop I'm trying to use for it is giving me a Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 14 error. I'm trying to get something along the lines of:
* *
* * * *
* * * * * *
* * * * * *
* * * * * * *
* * * * * * * * *
* * * * * * * * * *
* * * * * * * * * *
* * * * * * * * * *
* * * * * * * * * *
* * * * * * * * * *
* * * * * * * * * *
* * * * * * * * * *
- - - - - - - - - -
0 1 2 3 4 5 6 7 8 9
And this is what I have so far:
public static void VerticalHist()
{
int max = 0; // initialize max
int[] count = new int[10]; // make array to find max
for (int i = 0; i < 100; i++)
{
int rand = (int)(Math.random() * ((9 - 0) + 1)); // generate random values
count[rand]++;
}
for (int x : count) // find max
{
if (x > max)
max = x;
}
// System.out.println(max);
String[][] nums2 = new String[max][10]; // create 2d array for histogram
for (int x = max; x > 0; x--)
{
System.out.println();
for (int i = 0; i < nums2[x].length; i++)
{
if (count[i] > 0)
nums2[x][i] = "*";
}
}
for (int i = 0; i < max; i++) // print 2d array
{
System.out.println();
for (String n: nums2[i])
{
System.out.print(n);
}
}
}
My loop for inserting the * is giving me the error.
for (int x = max; x > 0; x--)
{
System.out.println();
for (int i = 0; i < nums2[x].length; i++)
{
if (count[i] > 0)
nums2[x][i] = "*";
count[i]--;
else
nums2[x][i] = "";
}
}
I'm trying to take each row, check each index to see if there needs to be an asterisk, (if so, put an asterisk, if not put a blank space) and do so for each row in the 2d array.

I think the problem might be in the for loop definition,
for (int x = max; x > 0; x--)
Can you try changing it to
for (int x = max-1; x >= 0; x--)
The reason is, since you define an array of size max and index starts from zero max is actually outside the array

The first thing is that this line
for (int x = max; x > 0; x--)
should be
for (int x = max-1; x >= 0; x--)
I would then change the logic to decide whether to add a "*" or a " " to this:
if (count[i] > x)
nums2[x][i] = "*";
else
nums2[x][i] = " ";
Note that this needs to be a space, not an empty string, otherwise your rows will be compressed.
With these changes you get output like this:
**********
**********
**********
**********
**********
**********
**********
** *******
* *** ***
* * * ***
* * **
* * *
*
Which is obviously upside down. You need to change this line:
for (int i = 0; i < max; i++) // print 2d array
to this
for (int i = max-1; i >= 0; i--) // print 2d array
Which produces:
* **
* **
* **
* ** *
* ** *
* *** * *
* *** * *
* *** * *
***** ***
****** ***
****** ***
****** ***
**********
**********
**********

How do I move the star into the place it belongs

That is my homework assignment in the link above. This is what I did so far:
import java.util.Scanner;
public class Bowling {
public static void recursionPins(int n, int t) {
if (n == 1) {
System.out.print("\t\t");
for (int i = 1; i <= t - 1; i++)
System.out.print(" ");
System.out.println("*");
} else {
recursionPins(n - 1, t);
for (int i = 1; i <= t - n; i++)
System.out.print(" ");
for (int i = 1; i <= n; i++)
System.out.print("* ");
System.out.println();
}
}
// main method
public static void main(String args[]) {
Scanner scan = new Scanner(System.in);
System.out.print("Enter number of rows of pins: ");
int n = scan.nextInt();
recursionPins(n, n);
}
}
When I run it, the first * is out of place and I'm not sure what the error is. The link below is a sample run of the program.
Enter number of rows of pins: 10
*
* *
* * *
* * * *
* * * * *
* * * * * *
* * * * * * *
* * * * * * * *
* * * * * * * * *
* * * * * * * * * *
I'm not sure how to move the star over.

Here in the base case:
if (n == 1) {
System.out.print("\t\t");
for (int i = 1; i <= t - 1; i++)
System.out.print(" ");
System.out.println("*");
}
You are printing two tabs and the required number of spaces. You need to remove System.out.print("\t\t");:
if (n == 1) {
for (int i = 1; i <= t - 1; i++)
System.out.print(" ");
System.out.println("*");
}
Output:
Enter number of rows of pins: 5
*
* *
* * *
* * * *
* * * * *

I need help in java pyramid code

I need help with this
1******
12*****
123****
1234***
12345**
123456*
1234567
Using 3 for loops this will be completed.
i tried this
public class Pattren {
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
int i,j,k;
for (i = 1; i <= 7; i++)
{
for (j = 1; j <= i; ++j)
{
System.out.print((j)+("\n"));
for (k = 7 - i; k >= 1; k--)
{
System.out.print("* ");
}
}
}
}
}
But there is some logical problem with it. I need improvement in thos code.
I got this output.
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

An easier version would be
int i,j;
for (i = 1; i <= 7; i++)
{
for (j = 1; j <= 7; ++j)
{
if (j <= i) {
System.out.print(j);
}
else {
System.out.print("*");
}
}
System.out.println();
}
Output
1******
12*****
123****
1234***
12345**
123456*
1234567

Below is a solution with much fewer lines of code:
public static void main(String[] args) {
StringBuilder sb = new StringBuilder();
String s = "";
for(int i=1; i<=7; i++){
s += i;
sb.append(String.format("%-7s", s).replace(" ", "*")).append("\n");
}
System.out.println(sb.toString());
}

Printing a Checkerboard - Code compiles but not outputting what I want

My code compiles, but it's not outputting what I want.
import java.util.Scanner;
public class Checkerboard {
public static void main(String[] args) {
int num, col;
//Scanner for input
Scanner keyboard = new Scanner(System.in);
//Get input
System.out.println("Enter a number: ");
num = keyboard.nextInt();
System.out.println("Enter the same number: ");
col = keyboard.nextInt();
for (int n = 0; n < num; n++) {
for (int c = 0; c < col; c++) {
System.out.print("* ");
}
System.out.println(" ");
}
}
}
It is outputting the pattern
(if N, C = 5)
* * * * *
* * * * *
* * * * *
* * * * *
* * * * *
What I want is
* * * * *
* * * * *
* * * * *
* * * * *
* * * * *
Any tips on how I could output what I want?

Insert
if(n%2==0){
System.out.print(" ");
before the inner loop.

Currently you are adding the space at the end of the line instead of at the beginning of the next line, and anyway, you only want to add the space not on each line, but only any other line.
for (int n = 0; n < num; n++) {
if (n % 2 == 0) {
System.out.print(" ");
}
for (int c = 0; c < col; c++) {
System.out.print("* ");
}
System.out.println();
}

Just change your inside for loop to
if(n%2==0){
System.out.print(" *");
} else {
System.out.print("* ");
}
Out put:
* * * * *
* * * * *
* * * * *
* * * * *
* * * * *

change inside for loop:
if(n%2==0){
System.out.print(" *");
} else {
System.out.print("* ");
}

I'm not sure how to add spaces to the small triangles to make it into a larger triangle

So basically my program will print this type of triangle when user input a number that module 8 and equal to 0. So a larger triangle is made out of smaller triangle with a base of 4. This is how a triangle look like when i input number 16:
* * * * * * * * * * * * * * * *
* * * * * * * * * * * *
* * * * * * * *
* * * *
* * * * * * * * * * * *
* * * * * * * * *
* * * * * *
* * *
* * * * * * * *
* * * * * *
* * * *
* *
* * * *
* * *
* *
*
but mine turned out like this:
* * * * * * * * * * * * * * * *
* * * * * * * * * * * *
* * * * * * * *
* * * *
* * * * * * * * * * * *
* * * * * * * * *
* * * * * *
* * *
* * * * * * * *
* * * * * *
* * * *
* *
* * * *
* * *
* *
*
I'm not so sure how to add the spaces. Can someone help me out? Here is my code:
...
System.out.println("Please enter the length:");
int length = scan.nextInt();;
//length must be longer than 2
if (length <= 1){
System.out.println("Sorry :(! Length must be 2 or higher");
}
//if user enter a number that can divide by 8 and has no remainder, then
//loop to print out a beautiful triangle
else if(length%8==0) {
int numOfTriangle = length/4;
System.out.println("Here is your beautiful triangle :D \n");
for (int rowOfTri = numOfTriangle; rowOfTri > 0; rowOfTri--){
for(int i = 0; i < rowOfTri; i++){
printBase();
}
System.out.println();
for(int i = 0; i < rowOfTri; i++){
printThree();
}
System.out.println();
for(int i = 0; i < rowOfTri; i++){
printTwo();
}
System.out.println();
for(int i = 0; i < rowOfTri; i++){
printOne();
}
System.out.println();
}
System.out.println();
}
//any other number will print a normal triangle
else{
System.out.println("Here is your beautiful triangle :D \n");
for (int i = 1; i <= length; i++){
for (int j = 1; j <= length; j++){
if (j < i){
System.out.print(" ");
} else {
System.out.print("*");
System.out.print(" ");
}
}
System.out.println();
}
}
//asking users if they want to print again
System.out.println("\nDo you want to print another triangle? Type Yes or No.");
//scan for string answer
String againChoice = scan.next();
//if answer start with Y or y then answer is Yes.
if(againChoice.startsWith("Y") || againChoice.startsWith("y")){
printAgain = true;
}
//if answer start with N or n then answer is No.
else if(againChoice.startsWith("N") || againChoice.startsWith("n")){
printAgain = false;
System.out.println("Bye!");
}
// set input to none again
} while (printAgain == true);
}
//methods to print a triangle
public static void printBase(){
System.out.print("* * * * ");
}
public static void printThree(){
System.out.print(" * * * ");
}
public static void printTwo(){
System.out.print(" * * ");
}
public static void printOne(){
System.out.print(" * ");
}
public static void printSpace(){
System.out.print(" ");
}
}

I've changed your printing code like this and it works properly:
else if (length % 8 == 0) {
int layer = 0;
int numOfTriangle = length / 4;
System.out.println("Here is your beautiful triangle :D \n");
for (int rowOfTri = numOfTriangle; rowOfTri > 0; rowOfTri--) {
for (int i = 0; i < layer; i++) {
printSpace();
}
for (int i = 0; i < rowOfTri; i++) {
printBase(layer);
}
System.out.println();
for (int i = 0; i < layer; i++) {
printSpace();
}
for (int i = 0; i < rowOfTri; i++) {
printThree(layer);
}
System.out.println();
for (int i = 0; i < layer; i++) {
printSpace();
}
for (int i = 0; i < rowOfTri; i++) {
printTwo(layer);
}
System.out.println();
for (int i = 0; i < layer; i++) {
printSpace();
}
for (int i = 0; i < rowOfTri; i++) {
printOne(layer);
}
System.out.println();
layer++;
}
System.out.println();