state flip-flop

According to a report in the state-run China Daily, the Beijing subway authorities are struggling to maintain supplies for a temporary slipper replacement program they've launched to help passengers who accidentally lose their flip-flops in rush-hour traffic.

据《中国日报》（China Daily）报道，北京地铁部门正在勉力维持便民拖鞋计划。有关部门推出这一计划的初衷是帮助高峰期上下地铁时意外将鞋掉入车厢和站台缝隙中的乘客。

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Some design examples show that the design of synchronous sequential circuits based on next state equations of flip-flops is of great advantage and practical significance.

通过设计实例表明，基于触发器次态方程设计同步时序电路具有一定的优点和实用意义。

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