C++最简单的字符串解码问题

Question

例如输入a3,解码后就是aaa；输入goo12le就是gooooooooooooole；输入XXX为结束。鄙人新手，点都不会.....麻烦来点简单的...初学者，不会高深的语法。最好是循环解决的....

Answer 1

    auto decode = [](string origin)
    {
        vectortarget;
        for (int pos, i = 0; i < origin.length(); )
        {
            if (origin[i] >= 'a'&&origin[i] <= 'z')
            {
                target.push_back(origin[i]);
                pos = i++;
            }
            else if (origin[i] >= '0'&&origin[i] <= '9')
            {
                int count = 0;
                while (origin[i] >= '0'&&origin[i] <= '9')
                {
                    count *= 10;
                    count+=origin[i++] - '0';
                }
                do { target.push_back(origin[pos]); } while (--count);
            }
            //if have other char
            else i++;
        }
        // last : vector -> string
        char *buffer = new char[target.size()+1];
        for (int i = 0; i < target.size(); i++)
            buffer[i] = target[i];
        buffer[target.size()] = '\0';
        auto result = string(buffer);
        delete[] buffer;
        return result;
    };

记录1个pos就行了。