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Properly outputting the total of a counter in Java

I have a working program that randomly generates a total of 100 asteriks arbitrarily on 10 rows. However, I am having a hard time printing the total of asteriks on each row. On the last line of code (which is commented out), I tried what I thought would be the first step to getting it to work. I need the output to look similar to this:
14| * *
13| * *
12| * * * *
11| * * * *
10| * * * * * *
9| * * * * * *
8| * * * * * * * *
7| * * * * * * * *
6| * * * * * * * * * *
5| * * * * * * * * * *
4| * * * * * * * * * *
3| * * * * * * * * * *
2| * * * * * * * * * *
1| * * * * * * * * * *
-------------------
0 1 2 3 4 5 6 7 8 9
Mine instead looks as followings:
0 |************
1 |*************
2 |******
3 |*************
4 |******
5 |*********
6 |*********
7 |*********
8 |************
9 |***********
Any assistance would be greatly appreciated
import java.util.Random;
public class QuestionTwoAssignmentOne2018 {
public static void main(String[] args) {
Random bytes = new Random(); //take this out of the loops as mentioned in the comments
int count = 100; //keep track of 100 '*'s
int arr[] = new int[100];
for (int a = 0; a < 100; a++) {
arr[a] = bytes.nextInt(10); //
}
for (int i = 0; i < 10 ; i++) {
int bcount = 0;
for (int a = 0; a < 100; a++) {
if (arr[a] == i)
bcount++;
}
System.out.print(i + " |");
for (int c = 0; c < bcount; c++ )
System.out.print("*");
System.out.println();
// System.out.println(bcount + " |"); // MY ATTEMPT
}
}
}
}

You cannot get desired output because you are using that commented line inside the loop.
import java.util.Random;
public class QuestionTwoAssignmentOne2018 {
private static final int NUM = 10;
public static void main(String[] args) {
Random bytes = new Random(); // take this out of the loops as mentioned
// in the comments
int count = 100; // keep track of 100 '*'s
int arr[] = new int[100];
for (int a = 0; a < 100; a++) {
arr[a] = bytes.nextInt(10); //
}
for (int i = 0; i < NUM; i++)
{
int bcount = 0;
for (int a = 0; a < 100; a++) {
if (arr[a] == NUM - i)
bcount++;
}
System.out.print(NUM - i + " |");
for (int c = 0; c < bcount; c++)
System.out.print("*");
System.out.println();
}
System.out.print(" "); // for better view
for (int i = 0; i < (NUM * 2) - 1 ; i++)
System.out.print("-");
System.out.println();
System.out.print(" "); // for better view
for (int i = 0; i < NUM; i++)
System.out.print(i + " ");
}
}
And I wrote the more generic code for you. You may just change constant NUM to arrange number of rows.

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());
}

2 Dimensional Arrays (Java) - Printing a Triangle with Alphabets in Cyclic order

The query was to write a Java method which prints the following triangle based on the input given (of the number of alphabets, on each side of the triangle).
public void triangle(int side);
Output expected:
triangle(3)
* * A * *
* F * B *
E * D * C
triangle(4)
* * * A * * *
* * I * B * *
* H * * * C *
G * F * E * D
I've come up with a method which does just that, but the code that I've written with my limited experience is with more number of for loops. Can any of you can review my code and come up with suggestions or optimized code for the same problem?
public void triangle(int input) {
int x = input;
int y = 2 * input - 1;
int mid = y / 2;
char character = 'A';
String[][] partitionArray1 = new String[x][y];
\\Following for loop will add letters on the side-1
for (int i = 0; i < x; i++) {
for (int j = 0; j < y; j++) {
if (i + mid == j) {
partitionArray1[i][j] = "" + character++;
} else {
partitionArray1[i][j] = "*";
}
}
}
\\Following for loop will add letters on the side-2 (horizontal)
for (int j = y - 2; j >= 0; j--) {
j--;
if (j >= 0) {
partitionArray1[x - 1][j] = "" + character++;
} else {
break;
}
}
\\Following for loop will add letters on the side-3
for (int i = x - 2; i >= 0; i--) {
for (int j = 0; j < y; j++) {
if ((i == mid - j) && (j < mid)) {
partitionArray1[i][j] = "" + character++;
}
}
}
for (int i = 0; i < x; i++) {
for (int j = 0; j < y; j++) {
System.out.print(partitionArray1[i][j] + "");
}
System.out.println();
}
}
Is there an algorithm available to answer such problems?

Try:
public static void triangle(int n) {
for (int i = 0; i < n; ++i) {
if (i == n-1) {
for (int j = 0; j < 2*n-1; ++j)
if (j % 2 == 0)
System.out.printf("%c ", 'A' + 2*n-2-j/2);
else
System.out.printf("* ");
System.out.println();
break;
}
for (int j = 0; j < 2*n-1; ++j) {
if (j == n-1+i)
System.out.printf("%c ", 'A'+i);
else if (j == n-1-i)
System.out.printf("%c ", 'A'+3*n-i-3);
else
System.out.printf("* ");
}
System.out.println();
}
}
The idea is to print row #n separately from the other. The rest of the row have exactly two element(except the first one which is a degenerated case) symmetrical with respect the center.
triangle(9);
* * * * * * * * A * * * * * * * *
* * * * * * * X * B * * * * * * *
* * * * * * W * * * C * * * * * *
* * * * * V * * * * * D * * * * *
* * * * U * * * * * * * E * * * *
* * * T * * * * * * * * * F * * *
* * S * * * * * * * * * * * G * *
* R * * * * * * * * * * * * * H *
Q * P * O * N * M * L * K * J * I

I was bored so i did it with one array
public static void mimi(int size){
int sizetab=size*size*2;
char res[] = new char[sizetab];
Arrays.fill(res,'*');
int pos=size-1;
int JumpGoRight=(2*size)+1;
int JumpGoLeft=2;
char letter='A';
boolean changed = false;
int nbLetters = size -1;
for (int s=size;s>1;s--)
nbLetters+=2;
int i=0;
while(i<(size-1)){
res[pos]=letter++;
pos+=JumpGoRight;
i++;
}
int limit=(sizetab-(size*2))+1;
while(i<nbLetters){
res[pos]=letter++;
pos-=JumpGoLeft;
if( !changed && (pos<limit) ){
JumpGoLeft=(size*2)-1 ;
changed=true;
}
i++;
}
int index = 0;
int doublesize=size*2;
for(char c: res){
if( ((++index)%doublesize)==0)
System.out.print('\n');
else
System.out.print(c);
}
}

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();