首页 > 代码库 > Problem Gas Station

Problem Gas Station

Problem Description:

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.

 

Solution:

 1     public int canCompleteCircuit(int[] gas, int[] cost) { 2      3         for (int i = 0; i < gas.length; i++) { 4             int total = 0; 5             int j = 0; 6             for (; j < gas.length; j++) { 7                 total += gas[(i+j) % gas.length] - cost[(i+j) % gas.length]; 8  9                 if (total < 0) {10                     i += j;11                     break;12                 }13             }14 15             if (j == gas.length) {16                 return i;17             } 18         }19 20         return -1;21     }