c++11 - Weird std::vector::reverse_iterator and string behavior -

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so have linear vector using store 2d value through class: want print values in reverse ... value (0,0) occupies bottom left , (max_x,max_y) occupies top right ... typical cartesian grid. here code:

 std::string ss="";  int i=0;     (std::vector<real>::reverse_iterator it= vector.rbegin(); it!=vector.rend();++it)     {         if (linechanger==max_x)         {             std::cout<<ss<<std::endl;             ss=""; linechanger=0;         }         ss=std::to_string(*it) +"|"+ ss;         linechanger++;     }

note: if not use string , print directly , fine , order reversed. member functions work in main code use std::fill fill vector value need (class function call). change few values e.g. @ (0,0) , (max_x,max_y) manually. (member functions ) filled 2.38 6x6 =36 sized vector changed. change first value accessed ( last in vector, first in reverse iterator) 3. , run program. output:

 2.380000|2.380000|2.380000|2.380000|2.380000|2.380000|  2.380000|2.380000|2.380000|2.380000|2.380000|2.380000|  2.380000|2.380000|2.380000|2.380000|2.380000|2.380000|  2.380000|2.380000|2.380000|2.380000|2.380000|2.380000|  2.380000|2.380000|2.380000|2.380000|2.380000|2.380000|

that whole size of vector, initial std::fill value... wrong? want avoid []operator .

notice sample output contains 30 values, not 36 values. loop prints string on iteration after contains max_x values. @ end of loop, last line of values in string variable never printed.


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