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Java lottery using arrays

I have to create a lottery game where you randomly generate six winning numbers simulating a lottery. Ask the user to enter six numbers and see if they win the lottery!
I have done a lot of it, but now im stuck. I am really new to java so forgive me. When it prompts to ask for another number it does it but it still displays it for the self-made lottery picks that display. Also, when displaying the numbers for the computer made lottery picks they are the same numbers over again that repeat and aren't 6 numbers. The counter doesn't work as well it maybe a little thing but i can't figure it out. Thank you
package arraysIntroduction;
import java.util.Scanner;
public class sizeQuestion {
public static void main(String[] args) {
Scanner in = new Scanner (System.in);
int [] user =new int [6];
int i;
//Fill user array
System.err.println("Welcome to Miwand's Lottery");
System.out.println("Please enter your 6 desiered number to enter the lottery");
System.out.println("Pick from 1 to 49");
for ( i=0;i<user.length;i++) // gets numbers until it equals 6
{
System.out.println("Number:");
user[i]= in.nextInt(); // Gets numbers from user
while (user[i] < 0 ) // if its a negative number tell user to enter again
{
System.err.println("Negative number, please enter again:");
user[i]=in.nextInt();
}
if (user[i] > 49) // if the number goes past 49 prompt again
{
System.err.println("Please enter numbers from 1 - 49");
}
}
//print out the numbers generated
for ( i=0;i < user.length; i++){
System.out.print(+user[i]+ " ");
}
System.out.println(" ");
int[] lottery = new int[6];
int guesses;
int counter=0;
int j;
int x;
{
for (j = 0; j < 6; j++) {
int randomNum = (int) (Math.random() *49 +1); // Random number created here.
for ( x = 0; x < j; x++) {
if (lottery[x] == randomNum) // Here, code checks if same random number generated before.
{
randomNum = (int) (Math.random() *49 +1);// If random number is same, another number generated.
}
lottery[j] = randomNum;
}
}
//prints out computer generated numbers
for (i = 0; i < lottery.length; i++){
for (x = 0; x< j; x++){
System.out.print(lottery[i] + " ");
if (user[i] == lottery[x] ){
counter++;
}
}
}
}
if (counter < 2){
System.out.println("Try again!");
}
if (counter == 3){
System.out.println("3 numbers matched! You won $300!");
}
if (counter == 4){
System.out.println("4 numbers matched! You won 500!");
}
if (counter == 5){
System.out.println(" 5 numbers matched! You won $1000!");
}
else if (counter == 6){
System.out.println("JACCKKKPOOOOTTTTTTT!!!!!! YOU WIN 1 MILLION DOLLARS!");
}
}
}

I saw multiple problems in your program.
First, the printout problem can be solved by moving the print statement from inner loop to outer loop
for (i = 0; i < lottery.length; i++) {
System.out.print(lottery[i] + " ");
for (x = 0; x < j; x++) {
if (user[i] == lottery[x]) {
counter++;
}
}
}
Also, you are not assigning the first random number correctly and it is always using the default, which is 0
Solution:
for (j = 0; j < 6; j++) {
int randomNum = (int) (Math.random() * 49 + 1); // Random number created here.
for (x = 0; x < j; x++) {
if (lottery[x] == randomNum) // Here, code checks if same random number generated before.
{
randomNum = (int) (Math.random() * 49 + 1);// If random number is same, another number generated.
}
}
lottery[j] = randomNum;
}
Plus, you didn't check if counter is equal to 2
Solution:
if (counter <= 2) {
System.out.println("Try again!");
}
And, the logic in "If random number is same, another number generated." may not be correct, since it may generate the same number again. You need a while loop to generate a new number until it is not equal to any of the generated numbers.
Another thing about coding style is that for any "for loops"
This :
int i=0;
for (i = 0; i < length; i++)
Should be replaced by this:
for (int i = 0; i < length; i++)

As I already said in the comments, you should move the print statement from the inner loop to the outer loop.
Your code should look like this:
for (i = 0; i < lottery.length; i++) { // outer loop
System.out.print(lottery[i] + " ");
for (x = 0; x < j; x++) { // inner loop
if (user[i] == lottery[x]) {
counter++;
}
}
}

Java output in lines of ten

I'm in a beginners java class and I have a quick question about the output statement on my array problem for week 5. So basically I have the core of the program down, but I'm supposed to output the result in lines of ten. I for some reason can not get it to work even with looking at similar posts on here. I'm a beginner and am pretty slow at putting 2 and 2 together when it comes to programming. Once I see it I have that ah-ha! moment and that's how this whole class has gone. I know I have to use the modulus, but in my trial and error I lost my way and have probably done more damage than good. Help would be appreciated.
Here is what I have and as you can tell I was trying something without modulus:
import java.util.*;
public class ArrayLoop
{
public static void main(String args[])
{
double alpha[] = new double[50];
*//Initialize the first 25 elements of the array (int i=0; i<25; i++)//*
for(int i = 0; i < 25; i++)
{
alpha[i]= i * i;
}
*//Initialize the last 25 elements of the array (i=25; i<50; i++)//*
for(int i = 25; i < 50; i++)
{
alpha[i]= 3 * i;
}
*//Print the element of the array*
System.out.println ( "The values are: " );
for (int i = 0; i < 50; i++)
System.out.println ( alpha[i] );
}
*//Print method to display the element of the array*
void print(double m_array[])
{
for(int i = 1; i < m_array.length; i++)
{
if(i % 10 == 0){;
System.out.println();
}else{
System.out.print(" ");
}
}
if (m_array.length % 10 != 0) {
System.out.println();
}
}
}

Um .. this isn't eloquent in the least but I tried to make the fewest changes to your existing code sample.
public class ArrayLoop {
public static void main(String args[]) {
double alpha[] = new double[50];
for (int i = 0; i < 25; i++) {
alpha[i] = i * i;
}
for (int i = 25; i < 50; i++) {
alpha[i] = 3 * i;
}
System.out.println("The values are: ");
for (int i = 0; i < 50; i++) {
System.out.print(alpha[i] + " ");
}
System.out.println();
System.out.println();
for (int i = 1; i < alpha.length; i++) {
if (i != 1 && i % 10 == 0) {
System.out.print(alpha[i - 1] + " ");
System.out.println();
} else {
System.out.print(alpha[i - 1] + " ");
}
}
System.out.print(alpha[49]);
}
}
Edit: A better condition would be ...
for (int i = 0; i < alpha.length; i++) {
if (i > 0 && i % 10 == 9) {
System.out.print(alpha[i] + " ");
System.out.println();
} else {
System.out.print(alpha[i] + " ");
}
}

You have to print the number first then decide whether to print space or newline by checking the modulus:
int arr[] = new int[50];
// Initialize array here
for (int i = 0; i < arr.length; i++) {
System.out.print(arr[i]);
if (i > 0 && (i + 1) % 10 == 0) {
System.out.println();
} else {
System.out.print(" ");
}
}

You have a couple of % 10 snippets in your code so I'm not entirely certain how that's "trying something without modulus" :-)
Having said that, modulus is exactly what you need, as per the following psuedo-code:
count = 0
for each item in list:
if count > 0 and (count % 10) == 0:
print end of line
print item
print end of line
In Java, you would use something like:
public class Test {
static public void main(String args[]) {
for (int i = 0; i < 24; i++) {
if ((i > 0) &&((i % 10) == 0)) {
System.out.println();
}
System.out.print ("" + i * 3 + " ");
}
System.out.println();
}
}
In other words, immediately before you print an item, check to see if it should be on the next line and, if so, output a newline before printing it.
Note that arrays in Java are zero based, so you need to start with an index of zero rather than one in your loops.
Now that's pretty close to what you have so you're on the right track but, for the life of me, I cannot see in your print() method where you actually print the item! That should be number one on your list of things to look into :-)
I urge you to try and work it out from the above text and samples but, if you're still having troubles after more than half an hour or so, the below code shows how I'd do it.
public class Test {
static void print (double m_array[]) {
for (int i = 0; i < m_array.length; i++) {
if ((i > 0) && ((i % 10) == 0))
System.out.println();
System.out.print (m_array[i] + " ");
}
System.out.println();
}
static public void main(String args[]) {
double[] x = new double[15];
for (int i = 0; i < x.length; i++)
x[i] = i * 3;
print (x);
}
}

java:generalized 8 queen to work for any initial state using depth first search [duplicate]

i am try to implement 8 queen using depth search for any initial state it work fine for empty board(no queen on the board) ,but i need it to work for initial state if there is a solution,if there is no solution for this initial state it will print there is no solution
Here is my code:
public class depth {
public static void main(String[] args) {
//we create a board
int[][] board = new int[8][8];
board [0][0]=1;
board [1][1]=1;
board [2][2]=1;
board [3][3]=1;
board [4][4]=1;
board [5][5]=1;
board [6][6]=1;
board [7][7]=1;
eightQueen(8, board, 0, 0, false);
System.out.println("the solution as pair");
for(int i=0;i<board.length;i++){
for(int j=0;j<board.length;j++)
if(board[i][j]!=0)
System.out.println(" ("+i+" ,"+j +")");
}
System.out.println("the number of node stored in memory "+count1);
}
public static int count1=0;
public static void eightQueen(int N, int[][] board, int i, int j, boolean found) {
long startTime = System.nanoTime();//time start
if (!found) {
if (IsValid(board, i, j)) {//check if the position is valid
board[i][j] = 1;
System.out.println("[Queen added at (" + i + "," + j + ")");
count1++;
PrintBoard(board);
if (i == N - 1) {//check if its the last queen
found = true;
PrintBoard(board);
double endTime = System.nanoTime();//end the method time
double duration = (endTime - startTime)*Math.pow(10.0, -9.0);
System.out.print("total Time"+"= "+duration+"\n");
}
//call the next step
eightQueen(N, board, i + 1, 0, found);
} else {
//if the position is not valid & if reach the last row we backtracking
while (j >= N - 1) {
int[] a = Backmethod(board, i, j);
i = a[0];
j = a[1];
System.out.println("back at (" + i + "," + j + ")");
PrintBoard(board);
}
//we do the next call
eightQueen(N, board, i, j + 1, false);
}
}
}
public static int[] Backmethod(int[][] board, int i, int j) {
int[] a = new int[2];
for (int x = i; x >= 0; x--) {
for (int y = j; y >= 0; y--) {
//search for the last queen
if (board[x][y] != 0) {
//deletes the last queen and returns the position
board[x][y] = 0;
a[0] = x;
a[1] = y;
return a;
}
}
}
return a;
}
public static boolean IsValid(int[][] board, int i, int j) {
int x;
//check the queens in column
for (x = 0; x < board.length; x++) {
if (board[i][x] != 0) {
return false;
}
}
//check the queens in row
for (x = 0; x < board.length; x++) {
if (board[x][j] != 0) {
return false;
}
}
//check the queens in the diagonals
if (!SafeDiag(board, i, j)) {
return false;
}
return true;
}
public static boolean SafeDiag(int[][] board, int i, int j) {
int xx = i;
int yy = j;
while (yy >= 0 && xx >= 0 && xx < board.length && yy < board.length) {
if (board[xx][yy] != 0) {
return false;
}
yy++;
xx++;
}
xx = i;
yy = j;
while (yy >= 0 && xx >= 0 && xx < board.length && yy < board.length) {
if (board[xx][yy] != 0) {
return false;
}
yy--;
xx--;
}
xx = i;
yy = j;
while (yy >= 0 && xx >= 0 && xx < board.length && yy < board.length) {
if (board[xx][yy] != 0) {
return false;
}
yy--;
xx++;
}
xx = i;
yy = j;
while (yy >= 0 && xx >= 0 && xx < board.length && yy < board.length) {
if (board[xx][yy] != 0) {
return false;
}
yy++;
xx--;
}
return true;
}
public static void PrintBoard(int[][] board) {
System.out.print(" ");
for (int j = 0; j < board.length; j++) {
System.out.print(j);
}
System.out.print("\n");
for (int i = 0; i < board.length; i++) {
System.out.print(i);
for (int j = 0; j < board.length; j++) {
if (board[i][j] == 0) {
System.out.print(" ");
} else {
System.out.print("Q");
}
}
System.out.print("\n");
}
}
}
for example for this initial state it give me the following error:
Exception in thread "main" java.lang.StackOverflowError
i am stuck, i think the error is infinite call for the method how to solve this problem.
any idea will be helpful,thanks in advance.
note:the broad is two dimensional array,when i put (1) it means there queen at this point.
note2:
we i put the initial state as the following it work:
board [0][0]=1;
board [1][1]=1;
board [2][2]=1;
board [3][3]=1;
board [4][4]=1;
board [5][5]=1;
board [6][6]=1;
board [7][1]=1;

[EDIT: Added conditional output tip.]
To add to #StephenC's answer:
This is a heck of a complicated piece of code, especially if you're not experienced in programming Java.
I executed your code, and it outputs this over and over and over and over (and over)
back at (0,0)
01234567
0
1 Q
2 Q
3 Q
4 Q
5 Q
6 Q
7 Q
back at (0,0)
And then crashes with this
Exception in thread "main" java.lang.StackOverflowError
at java.nio.Buffer.<init>(Unknown Source)
...
at java.io.PrintStream.print(Unknown Source)
at java.io.PrintStream.println(Unknown Source)
at Depth.eightQueen(Depth.java:56)
at Depth.eightQueen(Depth.java:60)
at Depth.eightQueen(Depth.java:60)
at Depth.eightQueen(Depth.java:60)
at Depth.eightQueen(Depth.java:60)
...
My first instinct is always to add some System.out.println(...)s to figure out where stuff is going wrong, but that won't work here.
The only two options I see are to
Get familiar with a debugger and use it to step through and analyze why it's never stopping the loop
Break it down man! How can you hope to deal with a massive problem like this without breaking it into digestible chunks???
Not to mention that the concept of 8-queens is complicated to begin with.
One further thought:
System.out.println()s are not useful as currently implemented, because there's infinite output. A debugger is the better solution here, but another option is to somehow limit your output. For example, create a counter at the top
private static final int iITERATIONS = 0;
and instead of
System.out.println("[ANUMBERFORTRACING]: ... USEFUL INFORMATION ...")
use
conditionalSDO((iITERATIONS < 5), "[ANUMBERFORTRACING]: ... USEFUL INFORMATION");
Here is the function:
private static final void conditionalSDO(boolean b_condition, String s_message) {
if(b_condition) {
System.out.println(s_message);
}
}
Another alternative is to not limit the output, but to write it to a file.
I hope this information helps you.
(Note: I edited the OP's code to be compilable.)

You asked for ideas on how to solve it (as distinct from solutions!) so, here's a couple of hints:
Hint #1:
If you get a StackOverflowError in a recursive program it can mean one of two things:
your problem is too "deep", OR
you've got a bug in your code that is causing it to recurse infinitely.
In this case, the depth of the problem is small (8), so this must be a recursion bug.
Hint #2:
If you examine the stack trace, you will see the method names and line numbers for each of the calls in the stack. This ... and some thought ... should help you figure out the pattern of recursion in your code (as implemented!).
Hint #3:
Use a debugger Luke ...
Hint #4:
If you want other people to read your code, pay more attention to style. Your indentation is messed up in the most important method, and you have committed the (IMO) unforgivable sin of ignoring the Java style rules for identifiers. A method name MUST start with a lowercase letter, and a class name MUST start with an uppercase letter.
(I stopped reading your code very quickly ... on principle.)

Try to alter your method IsValid in the lines where for (x = 0; x < board.length - 1; x++).
public static boolean IsValid(int[][] board, int i, int j) {
int x;
//check the queens in column
for (x = 0; x < board.length - 1; x++) {
if (board[i][x] != 0) {
return false;
}
}
//check the queens in row
for (x = 0; x < board.length - 1; x++) {
if (board[x][j] != 0) {
return false;
}
}
//check the queens in the diagonals
if (!SafeDiag(board, i, j)) {
return false;
}
return true;
}

How to find a specific number from a user set upperbound and lowerbound in java

The purpose of my code is to determine the number of times the number 3 appears between a range of numbers, the lower and upper bounds determined by the user.
So far, I can check if the number 3 is in the ten's place my using the modulus. But I am having trouble figuring out if a 3 resides in the hundreds, thousandths, etc. I know I need to use a nested loop, but I can't quite figure out how to code it.
Here is my code so far.
public class JavaThree {
public static void main (String [] args) {
int count = 0;
int num;
System.out.print("Enter lower end: ");
int lowerEnd = IO.readInt();
System.out.print("Enter upper end: ");
int upperEnd = IO.readInt();
if (lowerEnd > upperEnd) {
IO.reportBadInput();
return;
} else {
for(num = lowerEnd; num <= upperEnd; num++) {
if(num % 10 == 3) {
count = count + 1;
} else {
count = count;
}
}
}
IO.outputIntAnswer(count);
}
}

here is proper for loop for your task:
for(num = lowerEnd; num <= upperEnd; num++)
{
int nNum = num;
while (nNum > 0)
{
if( (nNum % 10) == 3)
count = count + 1;
nNum = nNum / 10;
}
}

Another solution, although not as efficient as the solution proposed #Ilya Bursov is to convert the number to a string and count the appearences of the char '3':
int threeCount = 0;
for (int num = lowerEnd; num < upperEnd; num++) {
String strNumber = String.valueOf(num);
for (int i = 0; i < strNumber.length(); i++) {
if (strNumber.charAt(i) == '3') {
threeCount++;
}
}
}

Java - Printing an empty square using nested loops

I am working on printing a quasi-empty square that looks like the example below (10 asterisks across and 10 down for the 2 columns):
**********
* *
* *
* *
* *
* *
* *
* *
* *
**********
My code cannot dynamically generate squares as specified by the user's input for the number of rows and columns (it is working for 10 rows and 10 columns, but as soon as I change the number to 20, the number of the asterisks does not change. The following is my code:
String STAR = "*";
String star1 = "**********";
int MAX = 10;
for (int row = 0; row <= MAX; row += 1 ) {
for (int col = 0; col <= MAX ; col += 10) {
if (row == 0 && col == 0)
System.out.println(star1);
if (row >= 1 && row <= 4)
System.out.println(STAR + " " + STAR);
if (row == 10 && col == 10)
System.out.println(star1);
}
}
Any help/advice is welcomed regarding the dynamism of the code.

String star = "*";
String space = " ";
int MAX = xxx;
for (int row = 0; row < MAX; row++) {
for (int col = 0; col < MAX; col++) {
if (row == 0 || row == MAX - 1) {
System.out.println(star);
} else if (col == 0 || col == MAX - 1) {
System.out.println(star);
} else {
System.out.println(space);
}
}
}

Look at your nested loop:
for (int col = 0; col <= MAX ; col += 10) {
So when col is 10, you're really only just iterating once... you might as well not have the nested loop at all.
Additionally, both star1 and the string literal with spaces have a fixed number of characters in them, clearly related to the number of columns.
I'm assuming this is homework, so I won't give any more hints than that to start with, but hopefully that'll get you thinking along the right lines...

You should change the 3 occurrences of 10 in your two for loops by the MAX variable, so when the user define another size, your for loop will take his input instead of the 10 value.

Also take a look at your last if statement there where it says if (row == 10 && col == 10) and think about it for a second. Once you have hit 10 rows and 10 columns, you are just going to print your final horizontal line of star1 regardless of what MAX is set too.

Like mentioned above, the nested for loop is unnecessary and can be inefficient if you plan to create larger rectangles in the future (not saying you're going to have to but try to stay away from nested for loops if you can). Instead, just print star1 before your loop begins and after it exits. The body of the loop should be simple enough. Hope this helps.

class Square
{
public static void main(String[] args)
{
String tenStars="**********";
String oneStar="*";
int count=0;
System.out.println(tenStars);
count++;
while(count<=8)
{
System.out.println(oneStar+" "+oneStar);
count++;
}
System.out.print(tenStars);
}
}

this should work
public static void hallowSquare(int side)
{
int rowPos, size = side;
while (side > 0)
{
rowPos = size;
while (rowPos > 0)
{
if (size == side || side == 1 || rowPos == 1 || rowPos == size)
System.out.print("*");
else
System.out.print(" ");
rowPos--;
}
System.out.println();
side--;
}
}

you can use something like this with one user input ... this is working
public static void drawSquare(int size)
{
for(int i=1; i<size ;i++)
System.out.print("*");
System.out.println("");
for(int i=0; i<50 ;i++)
{
System.out.print("*");
for(int j =0; j<size-3; j++)
System.out.print(" ");
System.out.println("*");
}
for(int i=1; i<size ;i++)
System.out.print("*");
}
public static void main(String[] args) {
// TODO Auto-generated method stub
drawSquare(50);
}
you should just create a class in put this inside your class and run it ... I hope this will help you ....

class Star8
{
public static void main(String[] args)
{
for(int i=1;i<=5;i++)
{
for(int j=1;j<=5;j++)
{
if(i==2||i==3||i==4 )
{
System.out.print("* *");
break;
}
else
{
System.out.print("*");
}
}
System.out.println();
}
}
}

Hope this helps, simplify your thinking mate. Think about the axis x and y and work by that logic. Make a nested loop on ur for loop that passes lines, in each case loop the number of
the size of square and print a space, after the nested loop print the "*".
> for (int b=0;b<ans*2-3;b++)
This nested loop has the max value of b because:
remember that while ur printing, each "*" is distanced from the other by a space, and remember u are only counting space between the first and last column. Meaning all space
between x=0 and x=squaresize, therefore max b should be the space between these 2 coords.
which are: squaresize * 2 /the 2 is for the added spaces/ -3/* -3 because u leave out the first coord(x=0),last coord(x=squaresize), AND 1 space added from the former loop.
import java.util.Scanner;
public class AsteriksSquare {
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner input= new Scanner(System.in);
int ans;
System.out.print("Enter the size of the side of the square: ");
ans=input.nextInt();
String ast="*";
if (ans>0 && ans<21){
for(int i=0;i<=ans-1;i++){
System.out.print("* ");
}
System.out.println("");
for(int i=1;i<=ans-2;i++){
System.out.print("*");
for (int b=0;b<ans*2-3;b++){
System.out.print(" ");
}
System.out.println("*");
}
for(int i=1;i<=ans;i++){
System.out.print("* ");
}
}
}
}

class square1
{
public static void main(String[] args)
{
String star = "*";
String space = " ";
int MAX = 5;
for (int row = 0; row < MAX; row++)
{
for (int col = 0; col < MAX; col++)
{
if (row == 0 || row == MAX - 1)
{
System.out.print(star);
} else if (col == 0 || col == MAX - 1)
{
System.out.print(star);
} else {
System.out.print(space);
}
}
System.out.println();
}
}
}

This code should do the trick.
package javaPackage;
public class Square {
public static void main(String [] args)
{
for (int i=0;i<=10;i++)
{
for (int j=0;j<=10;j++)
{
if(i==0||i==10){
System.out.print("x");
}
else if(j==0||j==10){
System.out.print("x");
}
else{
System.out.print(" ");
}
}
System.out.println();
}
}
}
If the interpreter sees that you're on the first and last line(i=0 and i=10), it will fill the row with x. Else, it will only print a x at the beginning and the end of the row.

you can use below two methods.
1) One with minimal line of code.
for (int i = 0; i <= 9; i++) {
if (i == 0 || i == 9) {
System.out.println("* * * *");
} else {
System.out.println("* *");
}
}
OR
2) With the help of two for loops
for (int i = 0; i <= 9; i++) {
for (int j = 0; j <= 9; j++) {
if (i == 0 || i == 9) {
System.out.print("*");
} else {
if (j == 0 || j == 9) {
System.out.print("*");
} else {
System.out.print(" ");
}
}
}
System.out.println();
}
Thanks,
Stuti

Here's another solution, a more versatile one. It lets you create a hollow rectangle of height "h" and width "w"
private static void hallowSquare(int h, int w)
{
for(int i=1; i<=h; i++)
{
for(int j=1; j<=w; j++)
{
if (j==1|| j==w || i==1 || i==h )
System.out.print("X");
else
System.out.print(" ");
}
System.out.println();
}
}

import java.util.Scanner;
class Star
{
public static void main(String...args)
{
Scanner sc = new Scanner(System.in);
System.out.print("Enter the row : ");
int row=sc.nextInt();
System.out.print("Enter the column : ");
int column=sc.nextInt();
for(int i=1;i<=column;i++)
{
System.out.print("*");
}
for(int i=row-2;i>=1;i--)
{
System.out.println();
System.out.print("*");
for(int k=1;k<=column-2;k++)
{
if(i<1)
{
break;
}
System.out.print(" ");
}
System.out.print("*");
}
System.out.println();
for(int i=1;i<=column;i++)
{
System.out.print("*");
}
}
}

I am hopeful the code below can help, used very simple coding and have the required result.
a=eval(input('Provide the height of the box: '))
b=eval(input('Provide the width of the box: '))
d=a-2
r=b-2
if a >= 1:
print('*'*b)
if a > 1:
for i in range(d):
print('*',end='')
for i in range(r):
print(' ',end='')
print('*')
print('*'*b,end='')
The result is: