longhorn

摘要： There areNgas stations along a circular route, where the amount of gas at stationiisgas[i].You have a car with an unlimited gas tank and it costscost[i]of gas to travel from stationito its next station (i+1). You begin the journey with an empty tank at one of the gas stations.Return the starting gas 阅读全文

摘要： Given a binary tree containing digits from0-9only, each root-to-leaf path could represent a number.An example is the root-to-leaf path1->2->3which represents the number123.Find the total sum of all root-to-leaf numbers.思路我觉得就是递归，如果遇到叶节点，返回叶节点的值，否则返回两个节点相加的结果。注意的是，我本来想用一个全局的静态的值表示总和，但是在leetcode 阅读全文