cmy203的博客

Then-queens puzzle is the problem of placingnqueens on ann×nchessboard such that no two queens attack each other.Given an integern, return all distinct solutions to then-queens puzzle.Each...

On a 2-dimensionalgrid, there are 4 types of squares:1represents the starting square. There is exactly one starting square. 2represents the ending square. There is exactly one ending square. ...

We can rotate digits by 180 degrees to form new digits. When 0, 1, 6, 8, 9 are rotated 180 degrees, they become 0, 1, 9, 8, 6 respectively. When 2, 3, 4, 5 and 7 are rotated 180 degrees, they become i...