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 05:29highload-churnerhighload-churnerScore: 2,042Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Nov 8, 2026 05:311,5659,645,839626,000020,480
2Nov 8, 2026 05:311,58510,021,051634,000020,480
3Nov 8, 2026 05:311,7179,687,644687,000020,480
4Nov 8, 2026 05:312,02011,501,047808,000020,480
5Nov 8, 2026 05:312,04210,178,762817,000020,480
6Nov 8, 2026 05:312,06710,179,884827,000020,480
7Nov 8, 2026 05:312,0709,837,879828,000020,480
8Nov 8, 2026 05:312,0709,791,490828,000020,480
9Nov 8, 2026 05:312,0779,820,513831,000020,480