C++ split

vector<string> split(string str,string pattern)
{
    vector<string> v;
    int pos = str.find(pattern);
    int size = str.size();
    // 截取最后一段
    str = str + pattern;
    while (pos != -1) {
        string sub = str.substr(0,pos);
        v.push_back(sub);
        str = str.substr(pos+1,size);
        pos = str.find(pattern);
    }
    return v;
}