Compilare: user.cpp: In function ‘int bfs()’: user.cpp:29:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<l[x].size();i++) { ^ user.cpp: In function ‘int bfs1()’: user.cpp:52:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<l[x].size();i++) { ^ user.cpp: In function ‘int main()’: user.cpp:78:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<l[n].size();i++) { ^