图的深度优先搜索

function Node(value) {
    this.value = value;
    this.neighbor = [];
}

let a = new Node("a");
let b = new Node("b");
let c = new Node("c");
let d = new Node("d");
let e = new Node("e");

a.neighbor.push(b);
a.neighbor.push(c);
b.neighbor.push(a);
b.neighbor.push(c);
b.neighbor.push(d);
c.neighbor.push(a);
c.neighbor.push(b);
c.neighbor.push(d);
d.neighbor.push(b);
d.neighbor.push(c);
d.neighbor.push(e);
e.neighbor.push(d);

//图的深搜比树的深搜多考虑一点是，图不能形成环

function deepSearch(node, target, path) {
    if (node === null) return false;
    if (path.indexOf(node) > -1) return false;//判断下当前节点有没有走过
    if (node.value === target) return true;
    path.push(node);//把当前节点放到已经查看过的路径里面

    let result = false;
    for (let i = 0; i < node.neighbor.length; i++) {
        result |= deepSearch(node.neighbor[i], target, path);
    }
    return !!result;
}

console.log(deepSearch(b, "n", []))