2019-08-16：DFS

[dorseysen]

请写一个简单的深度优先搜索（DFS）实现过程（与上题BFS一样实现对同一Tree的搜索）

[dorseysen]

//  2019-08-16：DFS

//  请写一个简单的深度优先搜索（DFS）实现过程（与上题BFS一样实现对同一Tree的搜索）

console.log(" ============== DFS =================== ");

class DFS {

    constructor (tree, target) {

        this.tree = tree;

        this.count = 0;

        this.flag = true;

        this.init(target);
    }

    init (target) {

        this.tree.forEach(item => {

            // 可以尝试一下这里的目标id传入11112跟12的区别，可以很简单的看出11112的this.count更小，深度优先
            // this.flag && this.deepFirst(item, "11112");

            this.flag && this.deepFirst(item, target);
        });

        // console.log("this.count = " + this.count);
    }

    deepFirst (node, target) {

        this.count ++;

        if(node.id === target) {

            // console.log(node.name);
            this.name = node.name;

            this.flag = false;

            return;
        }

        if( !!node.children && !!node.children.length ) {

            node.children.forEach(item => this.flag && this.deepFirst(item, target));
        }
    }
}
return new DFS(JSON.parse(JSON.stringify($state.Tree)), '1111').name;