When shoes slide across a floor, wave-like deformations of the sole can generate squeaking. The pitch of the squeak depends on the rate at which deformations are generated.
// 步骤3：从后往前遍历数组（反向遍历更易理解，每个元素只入栈/出栈一次）
，这一点在旺商聊官方下载中也有详细论述
Step 1: Connect to the Hierarchy (Your Local Area):
better: as a consumer-facing device, ATMs became part of the brand image of the