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Arrays of Arrays

Armstrong D

Joined: Apr 16, 2002
Posts: 7
can anybody explain this arrrays of arrays, i am getting confused with the nested for loops,
and what should i know in arrays of arrays as am preparing for the SCJP
class arr {
public static void main (String args[]) {
int twoD[][] = new int[2][3];
int i, j, k = 0;
for(i=0; i<2; i++)
for(j=0; j<3; j++) {
twoD[i][j] = k;
Thank you very much
Valentin Crettaz
Gold Digger

Joined: Aug 26, 2001
Posts: 7610
In this case we have a bi-dimensional array. It is kind of like a matrix 2x3 (2 rows - 3 columns).
int twoD[][] = new int[2][3];
The nested for loops are needed in order to access each cell of the matrix.
for(int i=0;i<2;i++) will traverse the first and second row.
for(int j=0;j<3;j++) will traverse the first, the second and the third column.
Each cell is assigned k (incremented at each iteration). The content of the bi-dimensional array after its initialization is:

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