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 11:54highload-churnerhighload-churnerScore: 2,630Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 19, 2026 11:562,4429,940,466977,00002,121,728stderr
2Oct 19, 2026 11:562,55010,029,1351,020,00002,121,728stderr
3Oct 19, 2026 11:562,56710,442,7031,027,00002,121,728stderr
4Oct 19, 2026 11:562,61510,415,7341,046,00002,121,728stderr
5Oct 19, 2026 11:562,63010,410,2971,052,00002,121,728stderr
6Oct 19, 2026 11:562,64711,649,0201,059,00002,121,728stderr
7Oct 19, 2026 11:562,65510,028,7671,062,00002,121,728stderr
8Oct 19, 2026 11:562,66210,419,3121,065,00002,121,728stderr
9Oct 19, 2026 11:562,68010,822,4911,072,00002,121,728stderr