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Solution to Sub-task: Finding Traversable Indices

Explore how to implement a method to check valid traversable indices in a two-dimensional JavaScript array. Understand the importance of bounds checking and value verification to ensure safe traversal within grid-based algorithms.

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Finding traversable indices

Before traversing any index, ensure that a given index is valid. For this, implement the method canTraverse like this:

Node.js
const Grid = require('./grid').gridClass;
// Create MazeSolver class below
class MazeSolver extends Grid{
    constructor(arr){
        super(arr); // initialize the grid
    }
    canTraverse(x,y){
        // check bounds
        if (x < 0 || y < 0)
            return false;
        else if (x >= this.grid.length)
            return false;
        else if (y >= this.grid[x].length)
            return false;
        // check if 0 or not
        else if(this.grid[x][y]===0)
            return false;
        else
            return true; // all passsed
    }
}
var arr = [
    [0, 1, 1, 1, 0],
    [0, 1, 1, 1, 0],
    [0, 1, 1, 1, 0],
    [0, 1, 1, 1, 0],
    [0, 1, 1, 1, 0],
]
var maze = new MazeSolver(arr);
console.log("can traverse -1, 1:", maze.canTraverse(-1,1));
console.log("can traverse 0, 0:", maze.canTraverse(0,0));
console.log("can traverse 1, -1:", maze.canTraverse(1,-1));
console.log("can traverse 1, 1:", maze.canTraverse(1,1));

For this method, look at the ...