LeetCode Gas Station

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.

class Solution {public:int canCompleteCircuit(vector<int> &gas, vector<int> &cost) {unsigned numOfStation = gas.size();if (numOfStation == 0)return -1;for (int i = 0; i < numOfStation; ++i) {int curval = 0;int curCount = 0;for (int j = i; j < i + numOfStation; ++j) {int temp = j % numOfStation;curval += gas[temp] - cost[temp];if (curval < 0) {break;}++curCount;}if (curCount == numOfStation) {return i;}}return -1;}};