2019-08-24

Author: JiayangWu

1165.单行键盘/1165-单行键盘.py

@@ -0,0 +1,16 @@
+class Solution(object):
+    def calculateTime(self, keyboard, word):
+        """
+        :type keyboard: str
+        :type word: str
+        :rtype: int
+        """
+        dic = dict()
+        for i, char in enumerate(keyboard):
+            dic[char] = i
+            
+        res, last_pos = 0, 0
+        for char in word:
+            res += abs(dic[char] - last_pos)
+            last_pos = dic[char]           
+        return res

1166.设计文件系统/1166-设计文件系统.py

@@ -0,0 +1,38 @@
+class FileSystem(object):
+
+    def __init__(self):
+        self.dic = dict()
+
+    def create(self, path, value):
+        """
+        :type path: str
+        :type value: int
+        :rtype: bool
+        """
+        if path in self.dic: 
+            return False
+        parent = path.split("/")
+        parent_path = ""
+        for i in range(1, len(parent) - 1):
+            # print parent, i
+            parent_path += "/" + parent[i]
+            # print parent_path
+            if parent_path not in self.dic:
+                return False
+        self.dic[path] = value
+        return True
+        
+
+    def get(self, path):
+        """
+        :type path: str
+        :rtype: int
+        """
+        return self.dic[path] if path in self.dic else -1
+        
+
+
+# Your FileSystem object will be instantiated and called as such:
+# obj = FileSystem()
+# param_1 = obj.create(path,value)
+# param_2 = obj.get(path)

1167.连接棒材的最低费用/1167-连接棒材的最低费用.py

@@ -0,0 +1,15 @@
+class Solution(object):
+    def connectSticks(self, sticks):
+        """
+        :type sticks: List[int]
+        :rtype: int
+        """
+        from heapq import * 
+        heapify(sticks)
+        res = 0
+        while len(sticks) > 1:
+            s1 = heappop(sticks)
+            s2 = heappop(sticks)
+            res += s1 + s2
+            heappush(sticks, s1 + s2)
+        return res

1168.水资源分配优化/1168-水资源分配优化.py

@@ -0,0 +1,60 @@
+
+class UnionFindSet(object):
+    def __init__(self, n):
+
+        self.roots = [i for i in range(n + 1)]
+        self.rank = [0 for i in range(n + 1)]
+        self.count = n
+
+    def find(self, member):
+        tmp = []
+        while member != self.roots[member]:
+            tmp.append(member)
+            member = self.roots[member]
+        for root in tmp:
+            self.roots[root] = member
+        return member
+
+    def union(self, p, q):
+        parentP = self.find(p)
+        parentQ = self.find(q)
+        if parentP != parentQ:
+            if self.rank[parentP] > self.rank[parentQ]:
+                self.roots[parentQ] = parentP
+            elif self.rank[parentP] < self.rank[parentQ]:
+                self.roots[parentP] = parentQ
+            else:
+                self.roots[parentQ] = parentP
+                self.rank[parentP] -= 1
+            self.count -= 1
+            
+class Solution(object):
+    def minCostToSupplyWater(self, n, wells, pipes):
+        """
+        :type n: int
+        :type wells: List[int]
+        :type pipes: List[List[int]]
+        :rtype: int
+        """
+        from heapq import *
+        for i, well in enumerate(wells):
+            pipes.append([0, i + 1, well])
+        
+        queue = []
+        ufs = UnionFindSet(n)
+        for start, end, cost in pipes:
+            queue.append([cost, start, end])
+            
+        heapify(queue)
+        res = 0
+        while ufs.count > 0:
+            
+            cost, start, end = heappop(queue)
+            # print ufs.roots, cost, start, end
+            if ufs.find(start) == ufs.find(end):
+                continue
+            res += cost
+            ufs.union(end, start)
+        return res
+        
+