public class Solution {
    public String longestCommonPrefix(String[] strs) {
        if(strs.length==0)return "";
        char[] str=strs[0].toCharArray();
        int Min=str.length;
        for(int i=1;i<strs.length;i++){
            char[] s=strs[i].toCharArray();
            int j=0;
            while(j<Min && j<s.length && s[j]==str[j])j++;
            Min = Min>j?j:Min;
        }
        return strs[0].substring(0,Min);
    }
}

C语言源代码（用时6ms）：

char* longestCommonPrefix(char** strs, int strsSize) {
    char* str=strs[0];
    int i,j;
    if(strsSize==0)return "";
    for(i=1;i<strsSize;i++){
        j=0;
        while(str[j] && strs[i][j] && str[j]==strs[i][j])j++;
        str[j]=0;
    }
    return str;
}

C++源代码（用时8ms）：

class Solution {
public:
    string longestCommonPrefix(vector<string>& strs) {
        if(strs.size()==0)return "";
        char* str=(char*)malloc(sizeof(char)*(strs[0].size()+1));
        for(int i=0;i<strs[0].size();i++){
            str[i]=strs[0][i];
        }
        str[strs[0].size()]=0;
        for(int i=1;i<strs.size();i++){
            int j=0;
            while(str[j] && strs[i][j] && str[j]==strs[i][j])j++;
            str[j]=0;
        }
        return string(str);
    }
};

Python源代码（用时66ms）：

class Solution:
    # @param {string[]} strs
    # @return {string}
    def longestCommonPrefix(self, strs):
        if len(strs)==0:return ""
        str=strs[0]
        Min=len(str)
        for i in range(1,len(strs)):
            j=0;p=strs[i]
            while j<Min and j<len(p) and p[j]==str[j]:j+=1
            Min = Min if Min<j else j
        return str[:Min]