# Create multidimension arrays : Array « Collections Data Structure « Java

Create multidimension arrays

```
// : c04:MultiDimArray.java
// Creating multidimensional arrays.
// From 'Thinking in Java, 3rd ed.' (c) Bruce Eckel 2002

import java.util.Random;

public class MultiDimArray {

static Random rand = new Random();

public static void main(String[] args) {
int[][] a1 = { { 1, 2, 3, }, { 4, 5, 6, }, };
for (int i = 0; i < a1.length; i++)
for (int j = 0; j < a1[i].length; j++)
System.out.println("a1[" + i + "][" + j + "] = " + a1[i][j]);
// 3-D array with fixed length:
int[][][] a2 = new int[2][2][4];
for (int i = 0; i < a2.length; i++)
for (int j = 0; j < a2[i].length; j++)
for (int k = 0; k < a2[i][j].length; k++)
System.out.println("a2[" + i + "][" + j + "][" + k + "] = "
+ a2[i][j][k]);
// 3-D array with varied-length vectors:
int[][][] a3 = new int[rand.nextInt(7)][][];
for (int i = 0; i < a3.length; i++) {
a3[i] = new int[rand.nextInt(5)][];
for (int j = 0; j < a3[i].length; j++)
a3[i][j] = new int[rand.nextInt(5)];
}
for (int i = 0; i < a3.length; i++)
for (int j = 0; j < a3[i].length; j++)
for (int k = 0; k < a3[i][j].length; k++)
System.out.println("a3[" + i + "][" + j + "][" + k + "] = "
+ a3[i][j][k]);
// Array of nonprimitive objects:
Integer[][] a4 = { { new Integer(1), new Integer(2) },
{ new Integer(3), new Integer(4) },
{ new Integer(5), new Integer(6) }, };
for (int i = 0; i < a4.length; i++)
for (int j = 0; j < a4[i].length; j++)
System.out.println("a4[" + i + "][" + j + "] = " + a4[i][j]);
Integer[][] a5;
a5 = new Integer[3][];
for (int i = 0; i < a5.length; i++) {
a5[i] = new Integer[3];
for (int j = 0; j < a5[i].length; j++)
a5[i][j] = new Integer(i * j);
}
for (int i = 0; i < a5.length; i++)
for (int j = 0; j < a5[i].length; j++)
System.out.println("a5[" + i + "][" + j + "] = " + a5[i][j]);
// Output test
int ln = 0;
for (int i = 0; i < a3.length; i++)
for (int j = 0; j < a3[i].length; j++)
for (int k = 0; k < a3[i][j].length; k++)
ln++;

}
} ///:~

```

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