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# Please explain me Array Reference Assignments for Multidimensional Array

Ami Ambre
Ranch Hand
Posts: 58
cat [][]my= {{new cat("F"),new cat("Z")},
{new cat("B"),new cat("R"),new cat("L")}};

cat []c=new cat[];

my=my[0];
//can't assign a 1-D array to a 2-D array.

my=my[0][0];
//can't assign a nonarray object to a 2-D array reference.

my[1]=my[1][2];
//can't assign a nonarray object to a 1-D array reference.

my[0][1]=c;
//can't assign an array object to a nonarray reference my[0][1] can only refer to a cat object

Dariusz Kordonski
Ranch Hand
Posts: 49

cat []c=new cat[]; // this won't work, you have to specify size of the instantiated array, e.g. new cat[5];

my=my[0];
//can't assign a 1-D array to a 2-D array.

my=my[0][0];
//can't assign a nonarray object to a 2-D array reference.

my[1]=my[1][2];
//can't assign a nonarray object to a 1-D array reference.

my[0][1]=c;
//can't assign an array object to a nonarray reference my[0][1] can only refer to a cat object[/QB]

What specifically you don't understand? There is one simple rule here: n-dimensional array reference of object x can only refer to instance of exactly n-dimensional array of object x (or subclass of x, since arrays are polymorphic) - period. In your case, cat[][] instance cannot be assigned to cat[] reference and vice versa, and so on...

Henry Wong
author
Marshal
Posts: 20902
76
Agreed. It looks like the comments does a very good job explaining everything. What is it that is not understood?

Henry