/in/P5.cpp: In function 'int main()':
/in/P5.cpp:18:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     while (start < str.length())//load
            ~~~~~~^~~~~~~~~~~~~~
/in/P5.cpp:21:52: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (end = start+1; str[end] != ' ' && end < str.length(); ++end);
                                                ~~~~^~~~~~~~~~~~~~
/in/P5.cpp:22:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if (end > str.length()) break;
             ~~~~^~~~~~~~~~~~~~
/in/P5.cpp:34:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if(j >= v.size())// if finish
            ~~^~~~~~~~~~~
/in/P5.cpp:40:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < v.size(); i ++)//"2k+1" items
                     ~~^~~~~~~~~~
/in/P5.cpp:44:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if (k >= v.size())// if finish
             ~~^~~~~~~~~~~
/in/P5.cpp:49:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i=0; i<vint.size(); i++) cout << vint[i] << " "; // vint is the vector containing the array
                   ~^~~~~~~~~~~~