LeetCode-Easy部分中标签为String 14. Longest Common Prefix

原题

Write a function to find the longest common prefix string amongst an array of strings.
举例：

"abab","aba","" 返回""

"abab","aba" 返回"aba"

代码分析

求各个字符串的最大公共前缀。先求出前2个最大公共前缀 cstr，然后拿它在之后字符依次比较，有一个不是，则丢弃 cstr 的最后一个字符。

实现代码

          public string LongestCommonPrefix(string[] strs)          {               if(strs==null || strs.Length==0)                   return "";               if (strs.Length == 1)                   return strs[0];               string longestPrefix = firstTwoStrs(strs);               if (longestPrefix.Length == 0)                  return "";              int i=2;              while(i < strs.Length)              {                  if (strs[i].IndexOf(longestPrefix) != 0)                  {                      longestPrefix =                       longestPrefix.Substring(0, longestPrefix.Length - 1);                      i = 1;                      if (longestPrefix.Length == 0)                          return "";                  }                  i++;              }              return longestPrefix;          }        //头两个字符串的公共串        private string firstTwoStrs(string[] strs)        {            if (strs.Length < 2) return "";            StringBuilder sb = new StringBuilder();            int len = strs[0].Length < strs[1].Length ? strs[0].Length : strs[1].Length;            for(int i=0;i<len;i++)            {                if (strs[0][i] == strs[1][i])                    sb.Append(strs[0][i]);                else                    break;            }            return sb.ToString();        }

更多string题目

http://blog.csdn.net/daigualu/article/details/69566863