Maximum limit for Java array

Question

I am trying to create a 2D array in Java as follows:

int[][] adjecancy = new int[96295][96295];

but it does not work with the following error:

JVMDUMP039I Processing dump event "systhrow", detail "java/lang/OutOfMemoryError" at 2017/04/07 11:58:55 - please wait.
JVMDUMP032I JVM requested System dump using 'C:\eclipse\workspaces\TryJavaProj\core.20170407.115855.7840.0001.dmp' in response to an event
JVMDUMP010I System dump written to C:\eclipse\workspaces\TryJavaProj\core.20170407.115855.7840.0001.dmp
JVMDUMP032I JVM requested Heap dump using 'C:\eclipse\workspaces\TryJavaProj\heapdump.20170407.115855.7840.0002.phd' in response to an event
JVMDUMP010I Heap dump written to C:\eclipse\workspaces\TryJavaProj\heapdump.20170407.115855.7840.0002.phd

A way to solve this problem is to increase the JVM memory, but I'm trying to provide code for an online encoding request. There it also fails, and I cannot change the settings there.

Is there any standard limit or guide for creating large arrays that should not exceed?

Answer 1

int[][] adjecancy = new int[96295][96295];

When you do this, you try to isolate the bits 96525*96525*32, which are almost 37091MB, which is about 37 gigs. It is very impossible to get memory from a PC just for Java.

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Answer 2

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Map<Integer, Map<Integer, Integer>> map = new HashMap<>();
map.put(27, new HashMap<Integer, Integer>()); // row 27 exists
map.get(27).put(54, 1); // row 27, column 54 has value 1.

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Answer 3

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1 int Java 4 , 37,09 .

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Answer 4

JVM . int 4 . , 1 , 1024 * 256 (1 = 1024 * 1024 ). , 2D- .

Answer 5

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96295 * 96295 * 4 ( ) = 37,090,908,100 = ~ 34,54 . JVM . .

, - -Xmx:

    Scanner scanner = new Scanner(System.in);
    while(true){
        System.out.println("Enter 2-D array of size: ");
        size = scanner.nextInt();

        int [][]numbers = new int[size][size];
        numbers = null;
    }

. -Xmx 512M → 2- ~ 10k +.

Typically, most online judges have a ~ 1.5-2GB bunch when evaluating applications.