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 listSep 13, 2026 21:09Andrew EpsteinAndrew EpsteinScore: 1,960Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Sep 13, 2026 21:141,8508,946,104740,000020,480
2Sep 13, 2026 21:141,8778,980,268751,000020,480
3Sep 13, 2026 21:141,8928,993,486757,000020,480
4Sep 13, 2026 21:141,9409,034,737776,000020,480
5Sep 13, 2026 21:141,9608,938,718784,000020,480
6Sep 13, 2026 21:142,0078,983,531803,000020,480
7Sep 13, 2026 21:142,0179,046,701807,000020,480
8Sep 13, 2026 21:142,2579,059,588903,000020,480
9Sep 13, 2026 21:142,3309,081,629932,000020,480