Leetcode.Longest Common Prefix

Longest Common Prefix

class Solution {
public:
    string longestCommonPrefix(vector<string> &strs) {
        if(strs.size() == 0) return string("");
        int strIdx = 0;
        //choose the smallest string first
        for(int i = 1; i < strs.size(); ++i)
            if(strs[i].size() < strs[strIdx].size()) strIdx = i;
        int commonLen = strs[strIdx].size();
        for(int i = 0; i < strs.size(); ++i)
        {
            if(i == strIdx) continue;
            int curLen = 0;
            for(int j = 0; j < strs[i].size() && j < commonLen; ++j)
            {
                if(strs[strIdx][j] == strs[i][j]) curLen++;
                else break;
            }
            commonLen = curLen;
        }
        return strs[strIdx].substr(0, commonLen);
    }
};