Create 합승택시요금.py

Author: KimGyuri875

week14/gyuri/합승택시요금.py

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+import heapq
+
+def solution(n, s, a, b, fares):
+    INF = int(1e9) 
+    graph = [[] for _ in range(n+1)]
+    for x, y, z in fares:
+        graph[x].append((z, y))
+        graph[y].append((z, x))
+
+    def dijkstra(start):
+        dist = [INF] * (n + 1)
+        dist[start] = 0
+        heap = []
+        heapq.heappush(heap, (0, start))
+        while heap:
+            value, destination = heapq.heappop(heap)
+            if dist[destination] < value:
+                continue
+
+            for v, d in graph[destination]:
+                next_value = value + v
+                if dist[d] > next_value:
+                    dist[d] = next_value
+                    heapq.heappush(heap, (next_value, d))
+        return dist
+
+    dp = [[]] + [dijkstra(i) for i in range(1, n+1)]
+    # print(dp)
+    answer = INF
+    for i in range(1, n+1):
+        answer = min(dp[i][a] + dp[i][b] + dp[i][s], answer)
+
+    return answer
+
+'''
+두명이 같은 위치에서 택시를 타고 같이 내린다.
+그 후 각자 택시를 타 최소 요금으로 각자 목적지에 도착한다.
+
+가중치가 있는 그래프 -> 다익스트라
+
+'''