The limitation on N was changed to reflect the actual test data. Instead of the old N < 10^600 the limitation was set to 0 < N < 10^300.

Note that this is not the limitation on the input, but rather on the output. The number given to the input has about twice as many digits, previously up to ~1200 digits, now up to ~600 digits, but the actual test data was always only up to ~600 digits. Edge case N=0 was also missing in the test data, and is now explicitly disallowed by the limitation.

New thorough tests were added within the new limitations. The time limit was reduced from 2.0 sec to 1.0 sec.

All solutions have been rejudged. 192 authors lost, and 12 other authors gained the Solved status for the problem.