Gas Station

Problem

There are N gas stations along a circular route, where the amount of gas at station i is gas[i].
You have a car with an unlimited gas tank and it costs cost[i] of gas to travel from station i to its next station (i+1). You begin the journey with an empty tank at one of the gas stations.
Return the starting gas station's index if you can travel around the circuit once, otherwise return -1.

Note:
The solution is guaranteed to be unique.

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Idea

• 暴力解法， 对于每一个起点，用两个变量curInde和nextIndex来跑，看看能不能跑到起点

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Solution

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