Dear reader, welcome to the next problem in the Recursion & Backtracking section named 'Queens Permutations - 2d As 2d - Queen Chooses'.
If somehow you have landed on this problem directly, then I must tell you that the train is on an intermediate station. The station of origin of our train was ' Queens Combinations - 2d As 2d - Box Chooses'.
Also, there is a strong prerequisite for this set of problems on permutations & combinations in 2D grid, which is permutations & combinations in 1D.
Important Links : Problem Link, Solution Video