Compilare: main.cpp: In function 'void drum(int, int)': main.cpp:50:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<v[nod].size();i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'void read()': main.cpp:18:12: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized] int x, y, c, nr, cnt; ^ main.cpp:18:9: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized] int x, y, c, nr, cnt; ^