c++ - Private variables somehow mysteriously change -

i have netbeans + qt + mingw.

could tell me going on in program. put breakpoint @ first loop in qtglass.cpp (marked breakpoint in comments below). arrow_n int signifying event of pressing key. want figure painted if press arrow key.

well, i'm in outer loop.

i = 5 falcon.get_x()+falcon.get_width() = 7 

then i'm in inner loop.

j = 5 falcon.get_y()+falcon.get_height() = 7 

at next iteration of inner loop falcon.get_x() = 261. @ next iteration of inner loop falcon.get_x() = 65797.

if stop debugging , start again, i'll same figures. so, there regularity in how these 261 , 65697 appear. how can mystery me current_x , current_y not changed since then. don't have setting methods changing them.

could me understand going on?

then start debugging.

figure.h

class figure: public qobject{     q_object public:     bool shape[4][4]; private:     int current_x;     int current_y;     int height;     int width;  public:     figure();     int testint;     int test[2];     int get_x();     int get_y();     int get_height();     int get_width(); 

figure.cpp

figure:: figure(){     current_x = 5;     current_y = 5;     height = 2;     width = 2; }  int figure:: get_x(){     return current_x; }  int figure:: get_y(){     return current_y; }  int figure::get_height(){     return height; }  int figure::get_width(){     return width; } 

qtglass.cpp

void qtglass::paintevent(qpaintevent *event) {     qpainter painter(this);     figure falcon;      glassredraw(painter);     painter.setpen(qpen(qt::red, 4));      if (arrow_n > 0) {         (int = falcon.get_x(); < (falcon.get_x()+falcon.get_width()); i++){ //breakpoint.             (int j = falcon.get_y(); j < (falcon.get_y()+falcon.get_height()); j++){                 if (falcon.is_cell_filled(i,j)){                     painter.fillrect(i * 30, j * 30, 29, 29, qbrush(qt::green, qt::solidpattern));                 }             }         }     }