• Breadth-First Search, Graph의 가까운 Node부터 탐색하는 방식
• Queue 기반으로 동작하며, Graph 레벨별로 탐색한다

function bfs(graph, current, visit) {
	let queue = []
	queue.push(current)

	visited[current] = true
	while (queue.length()) {
		const first = queue.shift()
		for (let i=0; graph[first].length; i++) {
			const value = graph[i]
			if (!visited[value]) {
				queue.push(value)
				visited[value] = true
			}
		}
	}
}

let visited = Array(8).fill(false)
let graph = [[], [2,3,8], [1,7], [1,4,5], [3,5], [7], [2,6,8], [1,7]]

bfs(graph, 0, visited)