This is a myprogramminglab problem. I'm given an array (a2d) and I need to determine if every row and column has the same number of elements as every other row and column. If it is then I set the boolean isSquare to true.

I have come up with the following code, but it doesn't like it and it isn't giving me any suggestions on how to improve it.

for(int row = 0; row < a2d.length; row++){
for(int col = 0; col < a2d[row].length; col++)
    if(a2d.length == a2d[row].length)
        isSquare = true;
    else
        isSquare = false;
}

Am I testing this the wrong way or is there a better way?

Thanks

• java

There is no need for 2 loops you should be able to do something like this (I'm not going to give the code since it's homework)

1. Save the length of the array (a2d.length)
2. Loop over all the rows
3. Check to see if the given row has the same length
4. if Not return false 
5. if you reach the end of the loop return true

for (int i = 0, l = a2d.length; i < l; i++) {
  if (a2d[i].length != l) {
    return false;
  }
}
return true;

you just need to ensure that all of the lengths of the 2nd dimension arrays are the same length as the first dimension array.

if(a2d.length == a2d[row].length)
    isSquare = true;
else
    isSquare = false;

If the last element passes this will return true always. Try this:

isSquare = true;
for(int row = 0; row < a2d.length; row++){
for(int col = 0; col < a2d[row].length; col++)
    if(a2d.length != a2d[row].length)
        isSquare = false;
}