LeetCode(134) Gas Station
2015-11-12 14:00
281 查看
题目
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.
分析
题目描述:有N个加油站点构成一个环状,每个站点ii加油量为gas[i]gas[i],从站点ii到站点i+1i+1需要耗费有两为cost[i]cost[i],现要求从哪个站点出发可以成功转一圈回到初始站点,返回该站点,若没有则返回-1;详细思路分析参考:算法分析网址
AC代码
class Solution { public: int canCompleteCircuit(vector<int> &gas, vector<int> &cost) { if (gas.size() == 0 || cost.size() == 0 || gas.size() != cost.size()) return -1; int total = 0, sum = 0, start = 0; for (int i = 0; i < gas.size(); ++i){ total += (gas[i] - cost[i]); if (sum < 0){ //发现油箱空了,从下一个站点尝试 sum = (gas[i] - cost[i]); start = i; } else sum += (gas[i] - cost[i]); } return total < 0 ? -1 : start; //用total判断start 是否是满足要求的解 } };
相关文章推荐
- ViewRootImpl 传递整个绘制过程
- LINUX 搭建sftp 服务器
- json.stringify与json.parse
- LeetCode(134) Gas Station
- CommonEqualityComparer<T>
- [LeetCode] Range Sum Query 2D - Immutable 二维区域和检索 - 不可变
- css3 复选框
- Xcode 真机测试 could not find developer disk image解决方法
- RocketMQ 源码分析
- SplitToList<T>
- C#怎样通过url调用接口
- 关于安卓HTTP请求用HttpUrlConnection还是HttpClient好
- Single Number II
- maven合并war包
- Mybatis自定义主键增长的一种方式
- Android google volley的源码研究记录
- ClassExtensions
- linux学习笔记(1):终端操作方法积累
- 零基础了解R语言
- iOS开发中使用FMDB来使程序连接SQLite数据库