java - How to convert a 1d array to 2d array?

Question

Say, I have a 1d array with 30 elements:

array1d[0] = 1  
array1d[1] = 2  
array1d[2] = 3  
.  
.  
.  
array1[29] = 30

How to convert the 1d array to 2d array?
Say 10x3?

array2d[0][0] = 1 array2d[0][1] =2 array2d[0][2] =3
.
.
.
array2d[9][0] = 28 array2d[9][1] =29 array2d[9][2] =30

Should I use a for loop?
But I cannot work it out.

Answer 1

int array2d[][] = new int[10][3];


for(int i=0; i<10;i++)
   for(int j=0;j<3;j++)
       array2d[i][j] = array1d[(j*10) + i];