Gas Station
There are n gas stations along a circular route, where the amount of gas at the i^th station is gas[i].
You have a car with an unlimited gas tank, and it costs cost[i] gas to travel from the i^th station to its next (i + 1)^th station. You begin the journey with an empty tank at one of the gas stations.
Given two integer arrays gas and cost, return the starting gas station's index if you can travel around the circuit once in the clockwise direction. Otherwise, return -1.
If there exists a solution, it is guaranteed to be unique.
Example 1
Input
gas = [1,2,3,4,5], cost = [3,4,5,1,2]Output
3Starting at station 3 provides enough gas to complete the full circuit and return to station 3.
Example 2
Input
gas = [2,3,4], cost = [3,4,3]Output
-1No station provides enough accumulated gas to travel around the circuit once.
Constraints
- n == gas.length == cost.length
- 1 <= n <= 10^5
- 0 <= gas[i], cost[i] <= 10^4
- The input is generated such that the answer is unique.
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