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Finding Conflicts
Let s start by doing some simple abstraction. To find a configuration in which there are no conflicts (where no queen may capture another), you first must define what a conflict is. And why not define it as a function while you re at it The conflict function is given the positions of the queens so far (in the form of a state tuple) and determines if a position for the next queen generates any new conflicts: def conflict(state, nextX): nextY = len(state) for i in range(nextY): if abs(state[i]nextX) in (0, nextYi): return True return False The nextX parameter is the suggested horizontal position (x coordinate, or column) of the next queen, and nextY is the vertical position (y coordinate, or row) of the next queen. This function does a simple check for each of the previous queens. If the next queen has the same x coordinate, or is on the same diagonal as (nextX, nextY), a conflict has occurred, and True is returned. If no such conflicts arise, False is returned. The tricky part is the following expression: abs(state[i]nextX) in (0, nextYi)

