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 3, 2026 05:55Karthik ReddyKarthik ReddyError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 3, 2026 05:550488,935,958455,374,00022,786,0002,113,536expected "50", got "A50 h26,20,20,18,25,12,25,23,15,19,22 big0 "
2Oct 3, 2026 05:550488,435,220455,393,00022,527,0002,113,536expected "50", got "A50 h24,14,24,16,12,24,25,24,23,26,13 big0 "
3Oct 3, 2026 05:550490,114,435456,509,00022,955,0002,113,536expected "87", got "A87 h26,12,31,18,18,27,17,18,21,23,22 big1 87@7389,3370 "