Is there any way of avoiding this block of code?

java

Solution

You can use a loop instead and define the bounds once. Something like:

int startRow = max(row - 1, 0);
int endRow = min(row + 1, width - 1);

int startCol = max(col - 1, 0);
int endCol = min(col + 1, height - 1);

for (int r = startRow; r <= endRow; r++)
   for (int c = startCol; c <= endCol; c++)
       if (r != row || c != col) //it looks like you want to skip this cell
           ray[r][c] += 1;

Alternatively, if the operation is reversible (as in this code, you are adding 1), you can simply reverse the operation for the middle cell after the loop. This would be more efficient since it eliminates (at most) 12 comparisons, provided the operation itself were simple:

int startRow = max(row - 1, 0);
int endRow = min(row + 1, width - 1);

int startCol = max(col - 1, 0);
int endCol = min(col + 1, height - 1);

for (int r = startRow; r <= endRow; r++)
   for (int c = startCol; c <= endCol; c++)
       ray[r][c] += 1;

//reverse the operation for the middle cell
ray[row][col] -= 1;

Problem

I am remaking minesweeper for practice, and wrote this bit of code to avoid IndexOutOfBounds errors. Is there a way of avoiding this so I don't have to explicitly write out an if statement every possible error? I thought of making each array 2 indexes larger, and just ignoring the first and last index. Am I missing something obvious? ``` if (row > 0 && col > 0) ray[row - 1][col - 1] += 1; if (row > 0) ray[row - 1][col] += 1; if (row > 0 && col < height - 1) ray[row - 1][col + 1] += 1; if (col > 0) ray[row][col - 1] += 1; if (col < height - 1) ray[row][col + 1] += 1; if (row < width - 1 && col > 0) ray[row + 1][col - 1] += 1; if (row < width - 1) ray[row + 1][col] += 1; if (row < width - 1 && col < height - 1) ray[row + 1][col + 1] += 1; ```

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