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up vote 1 down vote favorite

I have a 2d Boolean array and I want to dynamically create it's size based on the input coming in. For example: I have this string as the input "0-1 0-2 1-2 1-3 2-3". I split it on the dash and parsed it to an int. All those coordinates are positions in the Boolean array. When I initialize the array below for this example it works. But how could I initialize it dynamically in case the input changes? 

myArray = new boolean [4][4];
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1  
After splitting , you can have the max position from the coordinates. Based on this declare your array size. – Srinivas B Dec 5 '12 at 4:16
up vote 3 down vote accepted

If you must use a fixed-size array, you could find the max values for each coordinate separately, and use these values for the initialization:

int maxR = 0, maxC = 0;
for (String pair : pairs) {
    int r = ... // first part of the split
    int c = ... // second part of the split
    maxR = Math.max(maxR, r);
    maxC = Math.max(maxC, c);
}
boolean[][] myArray = new boolean[maxR][maxC];
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up vote 0 down vote

You could use ArrayLists instead. You can grow them as needed. (It's harder to shrink them.)

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up vote 0 down vote

split the string on space , " " It will give you total number of coordinates.

   String[] splitted = "0-1 0-2 1-2 1-3 2-3".split(" ");

Iterate through the array, split on "-" and get the maxX and maxY. This will give you the dimensions of the array.

The declaration will be like 

boolean[][] myArray = new boolean[maxX][maxY];

Hope it helps

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