Largest Square Submatrix of all 1's NoSIMD_C#

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 listJun 17, 2026 03:37Victor MerckléVictor MerckléError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Jun 17, 2026 03:3908,684,9681,493,00002,113,536expected "54", got "50 "
2Jun 17, 2026 03:392,0557,972,799822,00002,113,536
3Jun 17, 2026 03:392,2777,895,588911,00002,113,536
4Jun 17, 2026 03:392,3828,075,330953,00002,113,536
5Jun 17, 2026 03:392,4928,104,833997,00002,113,536
6Jun 17, 2026 03:393,1228,366,4041,249,00002,113,536
7Jun 17, 2026 03:393,2958,658,1721,318,00002,113,536
8Jun 17, 2026 03:393,4378,528,1551,375,00002,113,536
9Jun 17, 2026 03:393,9078,753,0191,563,00002,113,536