Merge pull request #37 from AlgoLeadMe/9-fnzksxl

9-fnzksxl

fnzksxl/README.md

@@ -10,4 +10,5 @@
 | 6차시 | 2024-02-14 | DP | [등굣길](https://school.programmers.co.kr/learn/courses/30/lessons/42898) | [#28](https://github.com/AlgoLeadMe/AlgoLeadMe-6/pull/28) |
 | 7차시 | 2024-02-18 | 그리디 | [구명보트](https://school.programmers.co.kr/learn/courses/30/lessons/42885) | [#30](https://github.com/AlgoLeadMe/AlgoLeadMe-6/pull/30) |
 | 8차시 | 2024-02-20 | DP | [동전1](https://www.acmicpc.net/problem/2293) | [#32](https://github.com/AlgoLeadMe/AlgoLeadMe-6/pull/32) |
+| 9차시 | 2024-02-23 | 그래프 | [순위](https://school.programmers.co.kr/learn/courses/30/lessons/49191) | [#37](https://github.com/AlgoLeadMe/AlgoLeadMe-6/pull/37) |
 ---

fnzksxl/그래프/순위.py

@@ -0,0 +1,39 @@
+from collections import deque
+
+def func(n, graph, degree):
+    for i in range(1, n+1):
+        q = deque()
+        q.append(i)
+
+        while q:
+            node = q.popleft()
+
+            for next_node in graph[node]:
+                _before = len(degree[i])
+                degree[i].add(next_node)
+
+                if _before == len(degree[i]):
+                    continue
+
+                q.append(next_node)
+
+def solution(n, results):
+    answer = 0
+    graph = [[] for _ in range(n+1)]
+    reversed_graph = [[] for _ in range(n+1)]
+    in_degree = [set() for _ in range(n+1)]
+    out_degree = [set() for _ in range(n+1)]
+
+    for win, defeat in results:
+        graph[win].append(defeat)
+        reversed_graph[defeat].append(win)
+
+    func(n, graph, out_degree)
+    func(n, reversed_graph, in_degree)
+
+
+    for i in range(1, n+1):
+        if len(out_degree[i])+len(in_degree[i]) == n-1:
+            answer += 1
+
+    return answer