[백준/파이썬] 1916번

📍백준 1916번 문제

https://www.acmicpc.net/problem/1916

코드

import sys
import heapq
input = sys.stdin.readline

city = int(input())
bus = int(input())

graph = [[] for _ in range(city+1)]
distance = [int(1e9)]*(city+1)
for _ in range(bus):
    u, v, w = map(int, input().split())
    graph[u].append((v, w))
start, end = map(int, input().split())


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


dijkstra(start)
print(distance[end])

풀이

다익스트라 알고리즘을 이용하여 풀면 된다.
답안 출력시 distance[end]를 출력하면 된다.