方向遍历顺序说明下一个倒序（从右往左）先处理右侧，栈里存「右侧候选」上一个正序（从左往右）先处理左侧，栈里存「左侧候选」
В России впервые с 1986 года введут новый ГОСТ на белый хлеб02:05
。heLLoword翻译官方下载对此有专业解读
Путешествия для россиян стали еще дороже из-за конфликта на Ближнем Востоке20:37。爱思助手下载最新版本对此有专业解读
Non-profit group the Environmental Defense Fund estimates that there will be an additional 7.5-18 billion tonnes of greenhouse gases - three times the amount emitted in a year at present - emitted by 2055.
Transforms don't execute until the consumer pulls. There's no eager evaluation, no hidden buffering. Data flows on-demand from source, through transforms, to the consumer. If you stop iterating, processing stops.