N-ary Tree

dfs.js

// Creating a sample n-ary tree
//        1
//      / | \
//     2  3  4
//    / \    |
//   5   6   7

class NaryTreeNode {
    constructor(value) {
        this.value = value;
        this.children = []; // An array to store children nodes
    }
}

function dfs(rootNode) {
    if (!root) {
        return [];
    }

    const stack = [rootNode]; 
    const result = []; // This will store the values in DFS order

    while (stack.length > 0) {
        const node = stack.pop();
        result.push(node.value);

        // Push all children onto the stack in reverse order
        // so that the leftmost child is processed first.
        for (let i = node.children.length - 1; i >= 0; i--) {
            stack.push(node.children[i]);
        }
    }

    return result;
}

const root = new NaryTreeNode(1);
const child1 = new NaryTreeNode(2);
const child2 = new NaryTreeNode(3);
const child3 = new NaryTreeNode(4);
const child4 = new NaryTreeNode(5);
const child5 = new NaryTreeNode(6);
const child6 = new NaryTreeNode(7);

root.children.push(child1, child2, child3);
child1.children.push(child4, child5);
child3.children.push(child6);

// DFS traversal
const dfsResult = dfs(root);
console.log(dfsResult); // Output: [1, 2, 5, 6, 3, 4, 7]