package com.leetcode.string;

/**

* Created by charles on 4/10/17.

* 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.

*/

public class LengthLastWord_58 {

public int lengthOfLastWord(String s) {

if (s == null || s.length() == 0) {

return 0;

}

int k = s.length() - 1;

while (k >= 0 && s.charAt(k) == ' ') {

k--;

}

if (k < 0) {

return 0;

}

int len = 0;

while (k >= 0 && s.charAt(k) != ' ') {

k--;

len++;

}

return len;

}

/** another easy solution using string api */

public int lengthOfLastWordII(String s) {

s = s.trim();

int lastSpaceIdx = s.lastIndexOf(' ') + 1;

return s.length() - lastSpaceIdx;

}

}