摘要：
[Problem] Given a knight in a chessboard (a binary matrix with 0 as empty and 1 as barrier) with a source position, find the shortest path to a destin 阅读全文
摘要：
[Problem] Given a undirected graph, a node and a target, return the nearest node to given node which value of it is target, return NULL if you can't f 阅读全文