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 19, 2026 11:58highload-churnerhighload-churnerScore: 1,860Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 19, 2026 11:591,6879,624,007675,000020,480
2Oct 19, 2026 11:591,75211,592,750701,000020,480
3Oct 19, 2026 11:591,8029,583,981721,000020,480
4Oct 19, 2026 11:591,85710,084,641743,000020,480
5Oct 19, 2026 11:591,86010,062,591744,000020,480
6Oct 19, 2026 11:591,8709,770,011748,000020,480
7Oct 19, 2026 11:591,8729,680,707749,000020,480
8Oct 19, 2026 11:591,89210,209,351757,000020,480
9Oct 19, 2026 11:592,1559,730,208862,000020,480