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🔥Gas Station: Circular Circuit Greedy BalanceMedium
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MediumDynamic Programming•Acceptance: 45.7%

Gas Station: Circular Circuit Greedy Balance

Targeted in FAANG & Tech OA:AmazonGoogle
Real-World Engineering Context
Used in electric vehicle fleet charging waypoint routing, spacecraft orbital propellant burn planning, and circular token transfer networks.
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]` of 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.

Sample Test Cases

Input: [[1,2,3,4,5],[3,4,5,1,2]]
Expected: 3
Input: [[2,3,4],[3,4,3]]
Expected: -1
Input: [[5],[4]]
Expected: 0

Constraints

  • n == gas.length == cost.length
  • 1 <= n <= 10^5
  • 0 <= gas[i], cost[i] <= 10^4
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