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 listNov 8, 2026 05:43highload-churnerhighload-churnerScore: 2,012Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Nov 8, 2026 05:441,5979,605,751639,000020,480
2Nov 8, 2026 05:441,6159,637,576646,000020,480
3Nov 8, 2026 05:441,9629,762,129785,000020,480
4Nov 8, 2026 05:441,9729,856,088789,000020,480
5Nov 8, 2026 05:442,01210,208,251805,000020,480
6Nov 8, 2026 05:442,03210,136,766813,000020,480
7Nov 8, 2026 05:442,03710,170,057815,000020,480
8Nov 8, 2026 05:442,3829,996,584953,000020,480
9Nov 8, 2026 05:442,56510,098,9041,026,000020,480