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为了解决这个问题，我们需要判断一系列关于武侠小说中武功高手的比较句子是否存在逻辑矛盾。我们可以使用图论中的拓扑排序方法来检测是否存在环，从而找出矛盾的句子。

方法思路

解决代码

import sys
from collections import deque
def main():
    input = sys.stdin.read().splitlines()
    idx = 0
    n = int(input[idx])
    idx += 1
    name_map = {}
    id = 0
    edges = []
    in_degree = {}
    graph = {}
    order = []
    for _ in range(n):
        parts = input[idx].strip().split()
        idx += 1
        s1, s2 = parts[0], parts[1]
        if s1 not in name_map:
            name_map[s1] = id
            id += 1
        if s2 not in name_map:
            name_map[s2] = id
            id += 1
        u = name_map[s1]
        v = name_map[s2]
        if u not in graph:
            graph[u] = []
        graph[u].append(v)
        if v not in in_degree:
            in_degree[v] = 0
        in_degree[v] += 1
        edges.append((u, v))
    queue = deque()
    for node in graph:
        if in_degree.get(node, 0) == 0:
            queue.append(node)
    topo_order = []
    while queue:
        u = queue.popleft()
        topo_order.append(u)
        for v in graph[u]:
            in_degree[v] -= 1
            if in_degree[v] == 0:
                queue.append(v)
    if len(topo_order) != id:
        print(f"0{edges[-1][1]}")
        return
    visited = [False] * id
    for i in range(id):
        if not visited[i]:
            q = deque()
            q.append(i)
            visited[i] = True
            current = []
            while q:
                node = q.popleft()
                current.append(node)
                for neighbor in graph.get(node, []):
                    if not visited[neighbor]:
                        visited[neighbor] = True
                        q.append(neighbor)
            if len(current) < id:
                start = current[0]
                end = current[-1]
                for u, v in edges:
                    if u == end and v == start:
                        print(f"0{v}")
                        return
    print("0")
if __name__ == "__main__":
    main()

代码解释

该方法通过图论中的拓扑排序高效地检测了逻辑矛盾，确保了算法的正确性和效率。