摘要：
ProblemApermutationof sizeNis a sequence ofNnumbers, each between 0 andN-1, where each number appears exactly once. They may appear in any order.There... 阅读全文
摘要：
ProblemA tree is a connected graph with no cycles.A rooted tree is a tree in which one special vertex is called the root. If there is an edge betweenX... 阅读全文
摘要：
ProblemShota the farmer has a problem. He has just moved into his newly built farmhouse, but it turns out that the outlets haven't been configured cor... 阅读全文