2020-01-22

JiayangWu · JiayangWu · commit e961b904c2c8 · 2020-01-22T22:36:04.000-05:00
diff --git a/1326.灌溉花园的最少水龙头数目/1326-灌溉花园的最少水龙头数目.py b/1326.灌溉花园的最少水龙头数目/1326-灌溉花园的最少水龙头数目.py
@@ -0,0 +1,26 @@
+class Solution(object):
+    def minTaps(self, n, ranges):
+        """
+        :type n: int
+        :type ranges: List[int]
+        :rtype: int
+        """
+        ivls = []
+        reach = [0 for _ in range(n + 1)]
+        for i in range(n + 1):
+            start, end = i - ranges[i], i + ranges[i]
+            end = min(end, n + 1)
+            start = max(start, 0)
+
+            for j in range(start, end):
+                reach[j] = max(end, reach[j])
+
+        res = 0
+        pos = 0
+        while pos < n:
+            if reach[pos] <= pos:
+                return -1
+            pos = reach[pos]
+            res += 1
+        return res
+            
