Leetcode-Length of Last Word

http://oj.leetcode.com/problems/length-of-last-word/

题目描述

Given a string s consists of upper/lower-case alphabets and empty space characters ' ', return the length of last word in the string.

If the last word does not exist, return 0.

Note: A word is defined as a character sequence consists of non-space characters only.

For example,

Given s = "Hello World",

return 5.

AC代码

请看: class Solution { public: bool ischar(char p) { return (p >= 'a' && p <= 'z') || (p >= 'A' && p <= 'Z'); } int lengthOfLastWord(const char *s) { // IMPORTANT: Please reset any member data you declared, as // the same Solution instance will be reused for each test case. int len = strlen(s); if(len < 1) return 0; int end = len - 1; while((end >= 0) && (s[end] == ' ')) end--; int begin = end; while((begin >= 0) && ischar(s[begin])) begin--;
return end - begin; } };