Update plates-between-candles.py

Author: kamyu104

Python/plates-between-candles.py

@@ -8,14 +8,14 @@ def platesBetweenCandles(self, s, queries):
         :type queries: List[List[int]]
         :rtype: List[int]
         """
-        left, prefix = [0]*len(s), [0]*len(s)
+        left, prefix = [0]*len(s), {}
         curr, cnt = -1, 0
         for i in xrange(len(s)):
             if s[i] == '|':
                 curr = i
                 cnt += 1
+                prefix[i] = cnt
             left[i] = curr
-            prefix[i] = cnt
         right = [0]*len(s)
         curr = len(s)
         for i in reversed(xrange(len(s))):