树数据处理

递归遍历树结构，根据条件删除树的某些节点

根据条件删除树的某些节点。示例中条件为：grade !== 1

function filterTree (data) {
            var newTree = data.filter(x => x.grade !== 1)
            newTree.forEach(x => x.children && (x.children = filterTree(x.children)))
            return newTree
        }