LeetCode 14 - Roman to Integer

Roman to Integer

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

My Code

class Solution {
public:
    string longestCommonPrefix(vector<string>& strs) {
        if (strs.empty())
            return "";
        else if (strs.size() == 1)
            return strs[0];

        int minLen = strs[0].size();
        for (int i = 0; i < strs.size() - 1; i++)
        {
            const string& str1 = strs[i];
            const string& str2 = strs[i+1];
            int curLen = 0;
            for (int j = 0; j < min(str1.size(), str2.size()); j++)
                if (str1[j] == str2[j])
                    curLen++;
                else
                    break;
            minLen = min(minLen, curLen);
        }
        //cout << "minLen: " << minLen << endl;

        return strs[0].substr(0, minLen);
    }
};

Runtime: 8 ms