Compilare: user.cpp: In function ‘void bfs()’: user.cpp:23:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<l[x].size();i++) { ^ user.cpp: In function ‘void bfs1()’: user.cpp:38:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<l[x].size();i++) { ^ user.cpp: In function ‘bool bfs2()’: user.cpp:57:34: 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:90:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<l[i].size();j++){ ^ user.cpp:99:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<l[n].size();i++) { ^