How arrays work in Java (illustration)
Array
An array is an expression that prepares a box for storing data side by side and puts it in and out. There are two types of arrays: one-dimensional arrays and multidimensional arrays. I will explain the mechanism of the array using an example.
One-dimensional array
Let's substitute 1,2,3,4,5 for each element of the array and display it.
Array1
class Array {
public static void main(String[] args) {
int[] a = new int[5];
for (int i = 0; i < a.length; i++){
a[i] = i + 1;
}
for (int i = 0; i < a.length; i++){
System.out.println("a[" + i + "] = " + a[i]);
}
}
}
【Execution result】
a[0]=1
a[1]=2
a[2]=3
a[3]=4
a[4]=5
Multidimensional array
Let's substitute 1,2,3,4,1,2,3,4 for each element of the array and display it.
Array2
class A2 {
public static void main(String[] args) {
int[][] x = new int[2][4];
for (int i = 0; i < 2; i++) {
for (int j = 0; j < 4; j++) {
x[i][j] = j + 1;
System.out.println("x[" + i + "][" + j + "] = " + x[i][j]);
}
}
}
}
【Execution result】
x[0][0] = 1
x[0][1] = 2
x[0][2] = 3
x[0][3] = 4
x[1][0] = 1
x[1][1] = 2
x[1][2] = 3
x[1][3] = 4
Recommended Posts