Compilare: user.cpp: In function ‘void clearNode(int, int)’: user.cpp:13:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < g[i].size(); ++j) ^ user.cpp: In function ‘void dfs(int)’: user.cpp:27:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < a[k].size(); ++i) ^ user.cpp:37:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < g[k].size(); i += 2) ^ user.cpp:50:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0 ; i < g[k].size(); ++i) ^ user.cpp:59:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < g[k].size() - 1; i += 2) ^