Editorial for DMOPC '21 Contest 7 P1 - Chika Grids


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Author: Riolku

Subtask 1 Just output any strictly increasing array.
Subtask 2 Just output any strictly increasing grid. A simple one would be to set position (i, j) to i + j, assuming i and j are one-indexed.
Subtask 3 It is optimal to greedily choose the smallest value for each cell, sweeping left to right. For instance, for: \displaystyle (0, 3, 0, 6) We greedily place a 1 in the first slot and a 4 in the third, to get: \displaystyle (1, 3, 4, 6)
Subtask 4 Apply the same strategy as subtask 3, except that we have to consider the cell below and to the left this time. A greedy approach still works.

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