balanced-array.py

class Solution:
 """
 @param sales: a integer array
 @return: return a Integer
 """
 def BalancedSalesArray(self, sales):
 # write your code here
 ls, rs = [], []
 for i in sales:
 if not ls:
 ls.append(i)
 else:
 ls.append(ls[-1] + i)
 for i in range(len(sales) - 1, -1, -1):
 if not rs:
 rs.append(sales[i])
 else:
 rs.append(rs[-1] + sales[i])
 for i in range(len(sales)):
 if ls[i] == rs[len(sales) - i - 1]:
 return i
 return -1
 
# easy: https://www.lintcode.com/problem/1793/