Compilare: main.cpp: In function 'void dfs(int)': main.cpp:32:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i<v[r].size(); i++) ~^~~~~~~~~~~~ main.cpp:43:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i<v[r].size(); i++) ~^~~~~~~~~~~~ main.cpp:50:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i<v[r].size(); i++) ~^~~~~~~~~~~~ main.cpp:53:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i<v[r].size(); i++) ~^~~~~~~~~~~~