Number (3): Everything in this light blue space must add up to 3. The answer is 1-2, placed vertically.
记忆技巧：找「更大」→ 弹掉 ≤ 当前的（栈顶保留比当前大的）；找「更小」→ 弹掉 ≥ 当前的；找「相等可接受」→ 用 < / ，否则用 <= / =。
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Venezuela's oil is also of poorer quality than its Saudi equivalent. Its sour, heavy crude is difficult to extract and refine, while its high sulphur content makes it corrosive to pipelines. A resurgence of Venezuela's industry could pose problems for Canada, which produces similarly viscous oil and exports much of it to the US, but analysts reckon the risk is minor.
即便竞争环境复杂多元，但中国市场仍然有着巨大拓展的空间和增长机会。从麦当劳到肯德基，其拓展策略都在指向同一个方向——高强度扩张不会暂停，但增长逻辑已从 “单纯拼开店数量” 转向 “规模与效率并重”。