Compilare: user.cpp: In function ‘void bfsx()’: user.cpp:45:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < g[k].size(); ++i) ^ user.cpp: In function ‘void bfsy()’: user.cpp:66:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < g[k].size(); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:91:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < ans.size(); ++i) ^