Longest Common Prefix

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

class Solution {
public:
    string longestCommonPrefix(vector<string> &strs) 
    {
        if(strs.size()==0) return "";
        
        string prefix="";
        int maxlen=strs[0].length();
        for(int i=1;i<strs.size();i++)
            if(strs[i].length()<maxlen)
                maxlen=strs[i].length();
        
        for(int i=0;i<maxlen;i++)
        {
            char c=strs[0][i];
            for(int j=1;j<strs.size();j++)
            if(strs[j][i]!=c)
                return prefix;
            prefix=prefix+c;
        }
        return prefix;
    }
};