Thank you. I read analysis. And want to solve problem with such algorithm :

1) make list of comparison ( first, second ) where we put pair ( first, second ) when we know that first < second.

2) look all permutations of { 1, 2, 3, 4, 5, 6 } ( with next permutation() in C++ ).

2.1) if current permutation does not satisfy to list of comparison then look next permutation.

2.2) if current permutation are satisfy to list of comparison then in this permutation find pair P[i] and P[i + 1] which not situated in list of comparison, compare them and add the result to list of comparison.

We continue this procedure untill permutations are not finished or we not compare more than 6 founded pairs ( P[i], P[i + 1]). At the end we found right permutation.

In this problem T <= 18 and all permutation of { 1, 2, 3, 4, 5, 6 } = 6! = 720 then O(18 * 780) = O (12960).

No more than 1 second. But I got TL. Here is my code. Can you say where my mistake or show another solution with realization?

Thank you.