Array in java

One dimensional  array: 

 Declaration of one dimensional array:

  type variable_name[];
  int test[] ; or  int[] test;

 Memory Allocation:

 test = new int[5];
 Or in one step

 int test[]  = new int[4];

 or int test[] = {12, 33,33,66}
Array length: int a = test.length;



Two dimensional array

int test[][]; int [][] test;
test = new int[2][4];

int test [][] = new int[2][4];

array length of two D array

int row = test.length;
int columns = test[i].length; 

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