init

AA.py

@@ -0,0 +1,42 @@
+import sys
+
+input_data = sys.stdin.read().split()
+
+n = int(input_data[0])
+m = int(input_data[1])
+
+graph = [[] for _ in range(n + 1)]
+ptr = 2
+
+for i in range(1, n + 1):
+    while True:
+        val = int(input_data[ptr])
+        ptr += 1
+        if val == 0:
+            break
+        graph[i].append(val)
+
+matching = [0] * (m + 1)
+
+def dfs(v):
+    if used[v]:
+        return False
+    used[v] = True
+    for to in graph[v]:
+        if matching[to] == 0 or dfs(matching[to]):
+            matching[to] = v
+            return True
+    return False
+
+for i in range(1, n + 1):
+    used = [False] * (n + 1)
+    dfs(i)
+
+result = []
+for to in range(1, m + 1):
+    if matching[to] != 0:
+        result.append((matching[to], to))
+
+print(len(result))
+for u, v in result:
+    print(u, v)