How can I add every element with the second and 3rd element after it in a grid (2D array)?-CodePudding

I have a 2D array and I'm trying to add element x to the two next elements in the grid horizontally while not going out of bounds.

For instance,

if this is my grid,

[1, 1, 1, 1, 1, 1]
[1, 1, 1, 1, 1, 1]
[1, 1, 1, 1, 1, 1]
[1, 1, 1, 1, 1, 1]
[1, 1, 1, 1, 1, 1]
[1, 1, 1, 1, 1, 1]

I want an output array that looks like

[3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3]

because every element is added with the next 2 elements after it.

Here had been my attempt so far:

        int n = 2;
        for (int x = 0; x < array.length; x   ) {
            for (int y = 0; y < array.length; y  ){
                for(int j = x 1; j <= x   n && j < array.length; j   ){
                l.add(array[x][y]   array[x   j][y]);
            }

However, when I try to run this, I get an index out of bound exception. I've tried to change the parameters of each variable but to no avail. What should I change in this?

CodePudding user response：

You could iterate the array and add the current value with the next two values if the current index is not the last index.

Assuming you have a 2D array of ints called "grid", you could do something like this:

int[][] newGrid = new int[grid.length][grid[0].length];
for (int i = 0; i < grid.length; i  ) {
    for (int j = 0; j < grid[0].length; j  ) {
        if (j < grid[0].length - 2) {
            newGrid[i][j] = grid[i][j]   grid[i][j   1]   grid[i][j   2];
        } else {
            newGrid[i][j] = grid[i][j];
        }
    }
}