[백준/파이썬] 1753번

📍백준 1753번 문제

https://www.acmicpc.net/problem/1753

코드

import heapq
import sys
input = sys.stdin.readline

v, e = map(int, input().split())
start = int(input())
graph = [[] for _ in range(v+1)]
INF = int(1e9)
distance = [INF] * (v+1)
for _ in range(e):
    n, v, w = map(int, input().split())
    graph[n].append((v, w))


def dijkstra(start):
    q = []
    heapq.heappush(q, (0, start))
    distance[start] = 0
    while q:
        dist, node = heapq.heappop(q)  # dist-거리, node-위치
        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)

for i in range(1, len(distance)):
    if distance[i] == INF:
        print('INF')
    else:
        print(distance[i])

풀이

다익스트라 알고리즘을 이용하여 풀면 된다.