Create most-stones-removed-with-same-row-or-column.py

Author: kamyu104

Python/most-stones-removed-with-same-row-or-column.py

@@ -0,0 +1,31 @@
+# Time:  O(n)
+# Space: O(n)
+
+class UnionFind(object):
+    def __init__(self, n):
+        self.set = range(n)
+
+    def find_set(self, x):
+        if self.set[x] != x:
+            self.set[x] = self.find_set(self.set[x])  # path compression.
+        return self.set[x]
+
+    def union_set(self, x, y):
+        x_root, y_root = map(self.find_set, (x, y))
+        if x_root == y_root:
+            return False
+        self.set[min(x_root, y_root)] = max(x_root, y_root)
+        return True
+
+
+class Solution(object):
+    def removeStones(self, stones):
+        """
+        :type stones: List[List[int]]
+        :rtype: int
+        """
+        MAX_ROW = 10000
+        union_find = UnionFind(2*MAX_ROW)
+        for r, c in stones:
+            union_find.union_set(r, c+MAX_ROW)
+        return len(stones) - len({union_find.find_set(r) for r, _ in stones})