結果

問題 No.160 最短経路のうち辞書順最小
ユーザー matsu7874matsu7874
提出日時 2015-11-29 19:25:34
言語 Python3
(3.12.2 + numpy 1.26.4 + scipy 1.12.0)
結果
AC  
実行時間 627 ms / 5,000 ms
コード長 3,365 bytes
コンパイル時間 111 ms
コンパイル使用メモリ 11,288 KB
実行使用メモリ 14,252 KB
最終ジャッジ日時 2023-10-12 05:46:26
合計ジャッジ時間 2,799 ms
ジャッジサーバーID
（参考情報） 		judge13 / judge11
このコードへのチャレンジ
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テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 21 ms
8,964 KB
testcase_01 AC 22 ms
8,912 KB
testcase_02 AC 21 ms
8,744 KB
testcase_03 AC 21 ms
8,972 KB
testcase_04 AC 41 ms
9,800 KB
testcase_05 AC 61 ms
10,712 KB
testcase_06 AC 84 ms
11,652 KB
testcase_07 AC 31 ms
9,276 KB
testcase_08 AC 32 ms
9,360 KB
testcase_09 AC 29 ms
9,324 KB
testcase_10 AC 34 ms
9,432 KB
testcase_11 AC 37 ms
9,424 KB
testcase_12 AC 33 ms
9,308 KB
testcase_13 AC 30 ms
9,412 KB
testcase_14 AC 33 ms
9,448 KB
testcase_15 AC 31 ms
9,396 KB
testcase_16 AC 30 ms
9,200 KB
testcase_17 AC 32 ms
9,404 KB
testcase_18 AC 31 ms
9,404 KB
testcase_19 AC 31 ms
9,228 KB
testcase_20 AC 32 ms
9,380 KB
testcase_21 AC 30 ms
9,328 KB
testcase_22 AC 31 ms
9,368 KB
testcase_23 AC 34 ms
9,348 KB
testcase_24 AC 34 ms
9,428 KB
testcase_25 AC 31 ms
9,244 KB
testcase_26 AC 31 ms
9,404 KB
testcase_27 AC 22 ms
8,864 KB
testcase_28 AC 627 ms
14,252 KB
testcase_29 AC 21 ms
8,868 KB
権限があれば一括ダウンロードができます

ソースコード

diff # 

import heapq
import collections


class Graph:

    def __init__(self, size):
        self.size = size
        self.graph = [[] for i in range(size)]

    def add_edge(self, source, target, cost):
        self.graph[source].append(self.Edge(target, cost))

    def add_bidirectional_edge(self, source, target, cost):
        self.add_edge(source, target, cost)
        self.add_edge(target, source, cost)

    def neighbors_of(self, n):
        res = []
        for e in self.graph[n]:
            res.append(e.target)
        return res

    def min_dist_dijkstra(self, s):
        dist = [float('inf')] * self.size
        dist[s] = 0
        q = [(0, s)]
        while q:
            node = self.Node(*heapq.heappop(q))
            v = node.id
            if dist[v] < node.dist:
                continue
            for e in self.graph[v]:
                if dist[e.target] > dist[v] + e.cost:
                    dist[e.target] = dist[v] + e.cost
                    heapq.heappush(q, (dist[e.target], e.target))
        return dist

    def min_path_dijkstra(self, s, t):
        dist = [float('inf')] * self.size
        prev = [-1] * self.size
        dist[s] = 0
        q = [(0, s)]
        while q:
            node = self.Node(*heapq.heappop(q))
            v = node.id
            if dist[v] < node.dist:
                continue
            for e in self.graph[v]:
                if dist[e.target] > dist[v] + e.cost:
                    dist[e.target] = dist[v] + e.cost
                    heapq.heappush(q, (dist[e.target], e.target))
                    prev[e.target] = v
                elif dist[e.target] == dist[v] + e.cost and prev[e.target] > v:
                    heapq.heappush(q, (dist[e.target], e.target))
                    prev[e.target] = v
            if v == t:
                break

        path = [t]
        while path[-1] > -1:
            path.append(prev[path[-1]])
        return path[:-1]

    def min_dist_queue(self, s):
        dist = [float('inf')] * self.size
        dist[s] = 0
        q = collections.deque()
        q.append(s)
        while q:
            v = q.popleft()
            for e in self.graph[v]:
                if dist[e.target] > dist[v] + e.cost:
                    dist[e.target] = dist[v] + e.cost
                    if e.cost == 0:
                        q.appendleft(e.target)
                    else:
                        q.append(e.target)
        return dist

    def __str__(self):
        res = ''
        for i in range(self.size):
            res += str(i)
            for e in self.graph[i]:
                res += ' ' + str(e.target)
            res += '\n'
        return res

    class Edge:

        def __init__(self, target, cost):
            self.target = target
            self.cost = cost

    class Node:

        def __init__(self, dist, i):
            self.dist = dist
            self.id = i

        def __cmp__(self, other):
            if self.dist < other.dist:
                return -1
            elif self.dist == other.dist:
                return 0
            else:
                return 1

n, m, start, goal = map(int, input().split())
g = Graph(n)
for i in range(m):
    a, b, c = map(int, input().split())
    g.add_bidirectional_edge(a, b, c)
print(' '.join(str(x) for x in g.min_path_dijkstra(goal, start)))
dist = g.min_dist_dijkstra(goal)
0