玩法四：8:1 超长图，无限拓展的画布
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」
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“A Supreme Court otherwise inclined to endlessly expand Trump’s authority just restricted his go-to tool, ruling that U.S. presidents do not have the power to unilaterally deploy tariffs and dole out punishment and favor to specific companies and economic sectors, friends and family, and entire countries,” said Lori Wallach of Rethink Trade.