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 06:50highload-churnerhighload-churnerScore: 2,025Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Nov 8, 2026 06:521,5879,685,149635,000020,480
2Nov 8, 2026 06:521,6209,622,757648,000020,480
3Nov 8, 2026 06:521,6259,862,640650,000020,480
4Nov 8, 2026 06:521,64512,005,588658,000020,480
5Nov 8, 2026 06:522,0259,791,794810,000020,480
6Nov 8, 2026 06:522,0409,860,151816,000020,480
7Nov 8, 2026 06:522,0429,785,171817,000020,480
8Nov 8, 2026 06:522,0459,817,396818,000020,480
9Nov 8, 2026 06:522,0659,808,373826,000020,480