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.
1 public class Solution { 2 public int canCompleteCircuit(int[] gas, int[] cost) { 3 int dif [] = new int[gas.length]; 4 for(int i=0;i<gas.length;i++){ 5 dif[i] = gas[i] - cost[i]; 6 } 7 int left = 0; 8 int sum = 0; 9 int start =0; 10 for(int i=0;i<gas.length;i++){ 11 left +=dif[i]; 12 sum += dif[i]; 13 if(sum<0){ 14 sum=0; 15 start = i+1; 16 } 17 } 18 return left<0?-1:start; 19 } 20 21 }
原文：http://www.cnblogs.com/krunning/p/3563988.html
