前k条最短路径的算法实例，用于最优航班的自动检索。有完整的可执行程序。KSP1使用了删除算法，KSP2使用了背离点算法。-Pre-k be the shortest path algorithm for example, automatic flight for optimal retrieval. Have a complete executable program. KSP1 delete algorithm used, KSP2 used deviate from the point al