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ISL 2022 C7

Lucy starts by writing ss integer-valued 2022-tuples on a blackboard. After doing that, she can take any two (not necessarily distinct) tuples v=(v1,…,v2022)\mathbf{v}=\left(v_{1}, \ldots, v_{2022}\right) and w=(w1,…,w2022)\mathbf{w}=\left(w_{1}, \ldots, w_{2022}\right) that she has already written, and apply one of the following operations to obtain a new tuple: v+w=(v1+w1,…,v2022+w2022)v∨w=(max⁡(v1,w1),…,max⁡(v2022,w2022))\begin{aligned} & \mathbf{v}+\mathbf{w}=\left(v_{1}+w_{1}, \ldots, v_{2022}+w_{2022}\right) \\ & \mathbf{v} \vee \mathbf{w}=\left(\max \left(v_{1}, w_{1}\right), \ldots, \max \left(v_{2022}, w_{2022}\right)\right) \end{aligned} and then write this tuple on the blackboard. It turns out that, in this way, Lucy can write any integer-valued 2022-tuple on the blackboard after finitely many steps. What is the smallest possible number ss of tuples that she initially wrote? (Czech Republic)

Official text Transcription from NuminaMath olympiads, checked word for word against the official paper. Quoted with source.

Official text: IMO 2022 Shortlist booklet, page 7.

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Solutions

Official solution Solution 1 by the IMO Problem Selection Committee

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