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1753.py
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1753.py
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import sys
import math
from collections import deque
import heapq
class Node():
def __init__(self, number):
self.number = number
self.edges = []
self.distance = math.inf
def __str__(self):
if math.isinf(self.distance):
return "INF"
else:
return f"{self.distance}"
def __gt__(self, other):
if self.distance != other.distance:
return self.distance > other.distance
else:
return self.number > other.number
def __eq__(self, other):
if self.distance != other.distance:
return False
else:
return self.number == other.number
V, E = [int(x) for x in input().split()] # Vertices, Edges
K = int(input()) # Starting node K
adj = [Node(x) for x in range(V+1)]
for i in range(E):
a, b, c = [int(x) for x in sys.stdin.readline().strip().split()]
adj[a].edges.append((a, b, c))
adj[K].visited = True
adj[K].distance = 0
q = []
for node in adj[1:]:
heapq.heappush(q, (node.distance, node))
while len(q) > 0:
curr = heapq.heappop(q)
if curr[0] >= curr[1].distance:
for edge in curr[1].edges:
dist_now = adj[edge[1]].distance
adj[edge[1]].distance = min(adj[edge[1]].distance, curr[1].distance + edge[2])
if adj[edge[1]].distance < dist_now:
heapq.heappush(q, (adj[edge[1]].distance, adj[edge[1]]))
for i in range(1, V+1):
print(adj[i])