Compilare: user.cpp: In function ‘void backtr(int)’: user.cpp:38:58: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(!viz[i] && graf[i].size()>0 && graf[i].size()<minim){ ^ In file included from /usr/include/c++/4.8/cassert:43:0, from user.cpp:6: user.cpp:45:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(graf[poz_min].size()==minim && minim); ^ user.cpp: In function ‘int main()’: user.cpp:120:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1;i<sol.size();i++) ^ user.cpp: In function ‘void backtr(int)’: user.cpp:43:11: warning: ‘poz_min’ may be used uninitialized in this function [-Wmaybe-uninitialized] int a=poz_min; ^