[파이썬] 1238 파티

import heapq
import sys
input = sys.stdin.readline
INF = int(1e9)

n, m, x = map(int, input().split())
graph = [[] for i in range(n + 1)]

for _ in range(m):
    a, b, c = map(int, input().split())
    graph[a].append((b, c))

def dijkstra(start):
    q = []
    heapq.heappush(q, (0, start))
    distance[start] = 0
    while q:
        dist, now = heapq.heappop(q)
        if distance[now] < dist:
            continue
        for i in graph[now]:
            cost = dist + i[1]
            if cost < distance[i[0]]:
                distance[i[0]] = cost
                heapq.heappush(q, (cost, i[0]))


ans = [0] * (n + 1)
for i in range(1, n + 1):
    distance = [INF] * (n + 1)
    dijkstra(i)
    if i == x:
        for j in range(1, n + 1):
            ans[j] += distance[j]
    else:
        ans[i] += distance[x]

print(max(ans[1:]))

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