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 12:48janwwwjanwwwScore: 2,062Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Nov 8, 2026 12:491,8759,760,469750,000020,480
2Nov 8, 2026 12:491,9209,787,675768,000020,480
3Nov 8, 2026 12:491,9859,792,049794,000020,480
4Nov 8, 2026 12:492,0529,799,716821,000020,480
5Nov 8, 2026 12:492,0629,814,564825,000020,480
6Nov 8, 2026 12:492,13211,191,015853,000020,480
7Nov 8, 2026 12:492,2409,925,811896,000020,480
8Nov 8, 2026 12:492,36010,040,759944,000020,480
9Nov 8, 2026 12:492,3759,977,793950,000020,480