You are right in indicating the possible problematic line. Surprised that you did it right in first half:
for (int c = 5; c >= 2 * a - 1; c -= 1) { // <==== here
System.out.print("*");
Pergunta
I got a problem to create a rhombus, my code here:
package random;
public class asd {
public static void main(String args[]) {
for (int j = 1; j <= 4; j++) {
for (int kong = 4 - j; kong >= 1; kong--) {
System.out.print(" ");
}
for (int xing = 1; xing <= 2 * j - 1; xing++) {
System.out.print("*");
}
System.out.println();
}
for (int a = 1; a <= 3; a++) {
for (int b = 1; b <= a; b++) {
System.out.print(" ");
}
for (int c = 5; c >= 1; c -= 2) { // <==== here
System.out.print("*");
}
System.out.println();
}
}
}
However, the output is:
*
***
*****
*******
***
***
***
I think the problem is in the code which I highlighted.
Solução 2
You are right in indicating the possible problematic line. Surprised that you did it right in first half:
for (int c = 5; c >= 2 * a - 1; c -= 1) { // <==== here
System.out.print("*");
Outras dicas
By using String#repeat
, introduced as part of Java-11, you can do it with a single loop.
public class Main {
public static void main(String[] args) {
int size = 9;
int midRowNum = size / 2 + 1;
for (int i = 1 - midRowNum; i < midRowNum; i++) {
System.out.println(" ".repeat(Math.abs(i)) + "*".repeat((midRowNum - Math.abs(i)) * 2 - 1));
}
}
}
Output:
*
***
*****
*******
*********
*******
*****
***
*
By increasing the amount of space by one character, you can also print a variant of the shape:
public class Main {
public static void main(String[] args) {
int size = 9;
int midRowNum = size / 2 + 1;
for (int i = 1 - midRowNum; i < midRowNum; i++) {
System.out.println(" ".repeat(Math.abs(i)) + "* ".repeat((midRowNum - Math.abs(i)) * 2 - 1));
}
}
}
Output:
*
* * *
* * * * *
* * * * * * *
* * * * * * * * *
* * * * * * *
* * * * *
* * *
*
Using Math.abs
will make it a lot easier:
import java.util.Scanner;
public class MakeDiamond {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
while (true) {
System.out.println("Let's Creat Diamonds");
System.out.println("If number increases Diamonds gets bigger. " +
"Please input number lager than 1 : ");
int user_input = sc.nextInt(); //gets user's input
System.out.println("");
int x = user_input;
int front_space = -5;
for (int i = 0; i < 2 * user_input + 1; i++) {
for (int a = front_space; a < Math.abs(i - user_input); a++) {
System.out.print(" ");
}
if (i < user_input + 1) {
for (int b = 0; b < 2 * i + 1; b++) {
System.out.print("* ");
}
} else if (i > user_input) {
for (int c = 0; c < 2 * x - 1; c++) {
System.out.print("* ");
}
x--;
}
System.out.print('\n');
}
System.out.println("\nRun Again? 1 = Run, 2 = Exit : ");
int restart = sc.nextInt();
System.out.println("");
if (restart == 2) {
System.out.println("Exit the Program.");
System.exit(0);
sc.close();
}
}
}
}
You can simplify your code by using two nested for loops and one if else statement.
int n = 4;
for (int i = -n; i <= n; i++) {
for (int j = -n; j <= n; j++)
if (Math.abs(i) + Math.abs(j) <= n)
System.out.print("*");
else
System.out.print(" ");
System.out.println();
}
Output:
*
***
*****
*******
*********
*******
*****
***
*