Gas Station Leetcode Python

The solution is guaranteed to be unique.

首先判断总的油够不够consume,如果总的油小于总的消耗那一定是走不完的。其次判断，过程中是否剩的油会小于0，如果小于0 那只能从下一个station开始。遍历一遍即可得到答案。

1. compare total gas and total cost, if             total gas<total cost 

return -1

2. iterate the whole station, rest+=gas[i]-cost[i] if rest<0, search start from the next i

return station

class Solution:
    # @param gas, a list of integers
    # @param cost, a list of integers
    # @return an integer
    def canCompleteCircuit(self, gas, cost):
        if sum(gas)<sum(cost):
            return -1
        else:
            pre=0
            rest=0
            station=0
            for index in range(len(gas)):
                rest+=gas[index]-cost[index]
                if rest<0:
                    pre+=rest
                    rest=0
                    station=index+1
        return station
        

Gas Station Leetcode Python

原文：http://blog.csdn.net/hyperbolechi/article/details/42879841