1. Grid
Conversion model, the inclusion and exclusion flanging solution.
2. Interestingly, the number of columns
Abstract model look, the odd term as abscissa, even term as ordinate, is come from the upper right corner and lower left corner of each of n * n matrix of step x <= y number of programs, the number is found Cattleya, about gcd , the line can screen out a prime number, easily can handle the number of minimum quality factor to obtain a rapid decomposition of each unique number, so that approximately points.
3. treehouse ladder
After the maximum value of the current of each put one of x and y coordinates of the point imagine, this matrix is the n * n from the lower left corner and top right corner of each walk step x> = y number of programs, the number of found Cattleya The only decomposition points about high-precision multiply.
4. The number of counts
Bare prufer, pay attention to all kinds of special sentence can be.
5. Obviously troubles
Or Prufer, the answer is selected from n-2 has the number of positions occupied by degrees, and then multiplied by the array including excessive power of the remaining positions of the point (point just put excessive rest position). Special attention was sentenced.
Overall conversion is important Cattleya various model numbers, the pull stack e.g., 1-1 sequence, and the like bracket matching.
prufer most important thing is not his own, the situation does not meet.