2.1.21—线性表—Gas Station

描述
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: e solution is guaranteed to be unique.

#include<iostream>using namespace std;int GasStation(int gas[], int cost[], int n){int left = 0;int index = 0;int sum = 0;for (int i = 0; i < n; i++){left += gas[i] - cost[i];sum += gas[i] - cost[i];if (left < 0){index = i;left = 0;}}if (sum < 0)return -1;elsereturn index+1;}int main(){const int n = 6;int gas[n] = { 2, 4, 7, 8, 6, 2 };int cost[n] = { 100, 5, 3, 6, 5, 1 };int index = GasStation(gas, cost, n);cout << index << endl;}