java - 遍历二维数组的下一个元素

Question

    //add adj nodes
    try{
        for(int r2 = 0; r2 < rows; r2++){
            for(int c2 = 0; c2 < cols; c2++){
                Node currentNode = nodeGrid[r2][c2];
                Node rightNode = nodeGrid[r2][c2+1];
                Node bottomNode = nodeGrid[r2+1][c2];

                if(!rightNode.isWall()){
                    currentNode.addNeighbor(rightNode);
                }
                if(!bottomNode.isWall()){
                    currentNode.addNeighbor(bottomNode);
                }
            }
        }
    }catch(ArrayIndexOutOfBoundsException e){
        System.out.println("no next node");
    }

您好，鉴于我有这个二维数组，并且我想访问下一个元素，我最终会达到索引越界，是否还有其他解决方法来访问下一个元素？

Answer 1

您必须更仔细地检查您的索引:

    for(int r2 = 0; r2 < rows; r2++){
        for(int c2 = 0; c2 < cols; c2++){
            Node currentNode = nodeGrid[r2][c2];
            Node rightNode = null;
            if (c2 < cols - 1) // the condition for the existence of a right node
                rightNode = nodeGrid[r2][c2+1];
            Node bottomNode = null;
            if (r2 < rows - 1) // the condition for the existence of a bottom node
                bottomNode = nodeGrid[r2+1][c2];

            if(rightNode != null && !rightNode.isWall()){
                currentNode.addNeighbor(rightNode);
            }
            if(bottomNode != null && !bottomNode.isWall()){
                currentNode.addNeighbor(bottomNode);
            }
        }
    }