问题描述：按照国际象棋的规则，车可以攻击与之处在同一行或同一列上的棋子。指南车是有方向的车。横向指南车可以攻击与之处在同一行上的棋子。纵向指南车可以攻击与之处在同一列上的棋子。指南车问题要求在m×n格的棋盘上放置指南车，并确定各指南车的攻击方向，使棋盘上不受指南车攻击的方格数最多。



编程任务：对于给定的m×n格的棋盘和2 个整数x 和y。整数x 表示棋盘上有x个规定方格应放置指南车，但攻击方向未定。整数y表示除了已规定放置位置的x个指南车外，还要在棋盘上放置y个指南车，其位置和攻击方向均未定。设计一个分支限界法，计算x+y 个指南车的放置方案，使棋盘上不受指南车攻击的方格数最多。

-Problem Descr iption: In accordance with the rules of chess, can attack with vehicles in the same column or row on the chess pieces. Guide to car yes car have direction. Horizontal guide in the car can attack with a pawn on the same line. Vertical guide in the car can attack with a pawn on the same row. Guide to car questions asked in the m × n grid of the chessboard placed guide vehicles, and to determine the guidelines for car attack direction, so that from the chessboard grid attacks cart number.



Programming tasks: For a given m × n grid of the chessboard and the two integers x and y. Integer x has x express chessboard grid of the provisions of the Guide should be placed car, but the direction of undetermined attack. Integer y that has been apart from the provisions of the x position to place a guide to the vehicle, but also in the board to place a guide y car, its location and direction of the attack were not set. Design of a branch and bound method to calculate x+ y个guide plac