Eragon20 Eragon20 - 4 days ago 5
Java Question

Simplification of successive 'if' statements in Java

I have a series of

if
statements, as shown below:

if (board[x+1][y]==true) {
ar+=1;
}
if (board[x][y+1]==true) {
ar+=1;
}
if (board[x-1][y]==true) {
ar+=1;
}
if (board[x][y-1]==true) {
ar+=1;
}
if (board[x+1][y+1]==true) {
ar+=1;
}
if (board[x+1][y-1]==true) {
ar+=1;
}
if (board[x-1][y+1]==true) {
ar+=1;
}
if (board[x-1][y-1]==true) {
ar+=1;
}


Is there a way to simplify/condense these statements with Java?

Answer

Simply loop around the position that you care about. Skipping the center of the "box".

Tip: You access a 2D array by row then column, or [y][x] (at least, that's how you'd translate the board from looking at the code).

for (int xDiff = -1; xDiff <= 1; xDiff++) {
    for (int yDiff = -1; yDiff <= 1; yDiff++) {
        if (xDiff == 0 && yDiff == 0) continue;
        if (board[y+yDiff][x+xDiff]) { 
            ar += 1;
        }
    }
}

Beware - Out of bounds exception is not handled

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