[JAVA]寻找最长公共前缀

法1：来源leetcode

class Solution {
    public String longestCommonPrefix(String[] strs) {
        String ret = "";
        
        if(strs.length == 0) return ret;
        if(strs.length == 1) return strs[0];
        
        ret = strs[0];
        
        for(int i = 1; i < strs.length; i++){
            while (!strs[i].startsWith(ret)){
                ret = ret.substring(0, ret.length()-1);
                if (ret.length() == 0){
                    return "";
                }
            }
        }
        return ret;
    }
}

法2：来源我

class Solution {
    public String longestCommonPrefix(String[] strs) {
        if(strs.length==0) return "";
        String s=new String();
        int i=0,j=1;
        while(true)
        {
            if(i>=strs[0].length()) return s;
            char t=strs[0].charAt(i);
            for(j=1;j<strs.length;++j)
            {
                if(i>=strs[j].length()||strs[j].charAt(i)!=t) break;
            }
            ++i;
            if(j==strs.length) s+=t;
            else return s;
        }
    }
}