北大ACM的代码，很经典的源代码 主流算法：搜索，动态规划，贪心，图论，数论，计算几何，组合数学，模拟，数据结构，博弈论　 -ACM code of Beijing University, is the source code of the mainstream of classical algorithms: search, dynamic programming, greedy, graph theory, number theory, computational geometry,