CareerCup

Magic square solution.
you can use magic squares and when a player inserts into a position just add it to previous sum. if sum == n(n^2+1)/2 then the player has won. the only problem is how to construct a magic square.
Ex for a 3x3 tic-tac-toe

8 1 6
3 5 4
4 9 2

when a player makes a move just add the value at that position. whenever the sum of three positions is 15 then the player won.

Whenever player places a coin, check for that particular row and column cell for the same coin. If the cell position is i == j, then the cell is in diagonal, then check for the diagonal. If the cell position is center then check both the diagonals.