This post is going to be really long, but I would be so glad if the community can help me.
This is a question from a former class test. I have to expect a similar one this time and I'm currently stuck. I'm new to Java and its concepts. The result of the test should look like this:
I'm facing multiple problems at once. I will try to be as specific as I can. First I will explain the task, which has given conditions that can't be changed.
The task Create an array field with 2 dimensions. The field should work with various sizes. Besides the size, the array field should contain the following pattern(see picture).
1.) Create an constructor that creates a rectangle array field from the parameter passed in, with to extra conditions.
1.1) If the parameter is less than 5, the field should be forced to appear as a 5/5 field.
1.2) If the paramter is more than 5 it should always appear as an n/n array.
public class Pattern {
char[][] field;
public Pattern(int n) {
// Here goes my code for creating the field
}
2.) Write a method that fills the constructor.
public void fillArray() {
// Here goes my code.
}
My approach so far
public Pattern(int n) {
field = new char[n][n];
int i, j;
if (field.length < 5) {
for (i = 1; i <= 5; i++) {
for (j = 1; j <= 5; j++) {
// ? what to do with the array here?
}
System.out.println();
}
}
public void fillArray() {
// no fu**ing idea...
}
public static void main (String[]args){
Pattern cross = new Pattern(2);
cross.fillArray();
System.out.println(cross);
}
Questions
1.) What value should be returned in the constructor?
2.) How can I access the object in the method and set a for loop, that gets the predefined field size? Should I use this ?
I'm sorry for my bad understanding on how to pass array information and execute these correctly.
You are putting what should be in fillArray in the constructor. The constructor should just be this:
public Pattern(int n) {
if (n < 5) {
field = new char[5][5];
} else {
field = new char[n][n];
}
}
And the two for loops should be in the fillArray method:
public void fillArray() {
// you should loop until field.length and field[x].length
for (int x = 0; x < field.length; x++) {
for (int y = 0; y < field[x].length; y++) {
// ...
}
}
}
Try to write your own logic of how to fill in the array.
If you are stuck, here is my solution:
for (int x = 0 ; x < field.length ; x++) {
for (int y = 0 ; y < field[x].length ; y++) {
/*
The '1' area can be represented by these inequalities:
x - y < 0
x + y < array.length - 1
The '2' area can be represented by these inequalities:
x - y < 0
x + y > array.length - 1
The '3' area can be represented by these inequalities:
x - y > 0
x + y > array.length - 1
The '4' area can be represented by these inequalities:
x - y > 0
x + y < array.length - 1
Everywhere that does not satisfy any of the inequalities are *s
*/
int xMinusY = x - y;
int xPlusY = x + y;
if (xMinusY < 0 && xPlusY < field.length - 1) {
field[x][y] = '1';
} else if (xMinusY < 0 && xPlusY > field.length - 1) {
field[x][y] = '2';
} else if (xMinusY > 0 && xPlusY > field.length - 1) {
field[x][y] = '3';
} else if (xMinusY > 0 && xPlusY < field.length - 1) {
field[x][y] = '4';
} else {
field[x][y] = '*';
}
}
}
// ...
// printing the array out:
for (int x = 0 ; x < field.length ; x++) {
for (int y = 0 ; y < field.length ; y++) {
System.out.print(field[x][y]);
}
System.out.println();
}