FindMinDepthOfTree.js

class Node {
	constructor(value = "", parent = undefined) {
		this.value = value;
		this.parent = parent;
		this.children = [];
		
		if (this.parent != undefined) {
			this.parent.children.push(this);
		}
	}
	
	description() {
		return this.value;
	}
}

const root = new Node(1);
const two = new Node(2, root);
const three = new Node(3, root);
const four = new Node(4, two);
const five = new Node(5, two);
const six = new Node(6, three);
const seven = new Node(7, three);
const eight = new Node(8, four);
const nine = new Node(9, five);
const ten = new Node(10, seven);
const eleven = new Node(11, eight);

let lowestValue = undefined;

function findMinDepth(node, currentDepth = 1) {
	const reachedLeafNode = node.children.length == 0;
	if (reachedLeafNode) {
		if (lowestValue === undefined || currentDepth < lowestValue) {
			lowestValue = currentDepth;
		}
		return;
	}
	
	node.children.forEach((childNode, i) => {
		findMinDepth(childNode, currentDepth + 1);
	});
}

findMinDepth(root);

console.log(`Minimum Depth is ${lowestValue}`)


// OUTPUT
// Minimum Depth is 3