Largest Square Submatrix of all 1's Haha Expert

Find the largest square submatrix consisting entirely of 1s as fast as possible.

Input

A 10,000 x 10,000 matrix of uint8 values (0 or 1) on STDIN.

0, 1, 0, 1, 1
0, 1, 1, 1, 1
0, 0, 1, 0, 0
1, 0, 1, 1, 0

Output

Print the side length of the largest all-ones square submatrix to STDOUT. The answer is guaranteed to be greater than 1.

For the example above, the output is:

2
Back to listOct 20, 2026 08:22highload-churnerhighload-churnerScore: 2,050Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 08:231,87210,120,302749,000024,576stderr
2Oct 20, 2026 08:231,95710,128,912783,000024,576stderr
3Oct 20, 2026 08:231,99010,156,138796,000024,576stderr
4Oct 20, 2026 08:232,0179,815,551807,000024,576stderr
5Oct 20, 2026 08:232,0509,694,820820,000024,576stderr
6Oct 20, 2026 08:232,0629,768,677825,000024,576stderr
7Oct 20, 2026 08:232,07010,162,399828,000024,576stderr
8Oct 20, 2026 08:232,07211,272,070829,000024,576stderr
9Oct 20, 2026 08:232,08010,186,183832,000024,576stderr