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 06:27highload-churnerhighload-churnerScore: 1,757Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Nov 8, 2026 06:281,6159,613,006646,000024,576stderr
2Nov 8, 2026 06:281,6609,701,197664,000024,576stderr
3Nov 8, 2026 06:281,6659,645,946666,000024,576stderr
4Nov 8, 2026 06:281,66711,329,422667,000024,576stderr
5Nov 8, 2026 06:281,7579,658,781703,000024,576stderr
6Nov 8, 2026 06:282,0479,763,033819,000024,576stderr
7Nov 8, 2026 06:282,1309,945,641852,000024,576stderr
8Nov 8, 2026 06:282,1429,885,966857,000024,576stderr
9Nov 8, 2026 06:282,16210,378,085865,000024,576stderr