智力游戏，用方格代表街道房屋，要求输入信息之后计算最多可以有多少枪手，同时存在在城市中而不会相互射击，原来是ACM竞赛的赛题-Intellectual games, with the street grid on behalf of housing, asked to enter information after the calculation of maximum number of gunmen, at the same time the existence in the city and